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WorksheetsVật Lý Kỹ Thuật Quiz
Total questions: 118
Worksheet time: 1hrs 17mins
What property does uniform linear motion have?
The coordinates of the point mass are a linear function of time.
The distance traveled decreases over time.
Velocity increases over time.
Acceleration is always positive.
When two objects of different masses are dropped from a height in a vacuum, which conclusion is correct?
Both objects hit the ground at the same time.
The heavier object hits the ground before the lighter one.
The heavier object hits the ground after the lighter one.
It is indeterminate which object hits the ground first.
In which case does an object not experience the effect of a net force (or any force)?
Uniform motion.
Uniform circular motion.
Accelerating uniformly.
Decelerating uniformly.
Free fall is defined as
the fall of objects only under the influence of gravity.
the fall of objects only under the influence of drag force.
the fall of a leaf in the air.
the fall of a steel ball in the air.
What property does the momentum of an object in uniform linear motion have?
Constant.
Changing direction, constant magnitude.
Constant direction, changing magnitude.
Changing direction and magnitude.
Which object's fall in the air can be considered free fall?
An object with low density.
An object with high density.
A small object.
A large object.
A car is decelerating with an initial speed of 18 km/h. In the 5th second from the start of deceleration, the car travels a distance of 2.75 m. What is the magnitude of the car's acceleration?
0.5 m/s²
1.0 m/s²
1.5 m/s²
2.0 m/s²
In the last 2 seconds, an object in free fall travels a distance of 40 m. Take g = 10 m/s².
What is the magnitude of the acceleration of the car?
0.5 m/s²
1.0 m/s²
1.5 m/s²
2.0 m/s²
From the last 2 seconds, the object fell freely for a distance of 40 m. From what height was the object released?
22.5 m
45 m
90 m
180 m
A stone is thrown straight down from a height of 75 m with an initial velocity of 10 m/s. If g = 10 m/s², neglecting air resistance, how long does it take for the stone to fall to the ground?
1 s
3 s
5 s
7 s
From a height of 7.5 m, a ball is thrown at an angle of 45° with an initial velocity of 10 m/s. How far from the throwing position will the ball land horizontally?
5 m
10 m
15 m
20 m
From a height of 80 m, a person throws an object horizontally with an initial velocity. If g = 10 m/s², how long does it take for the object to hit the ground?
4 s
6 s
8 s
10 s
Given the system as shown: mA = 5 kg; mB = 2 kg; α = 30°; k = 0.1. If g = 10 m/s², what is the acceleration of the system?
0.1 m/s²
0.2 m/s²
0.3 m/s²
0.4 m/s²
A mass of 20 kg is pulled sliding on a horizontal surface by a force making an angle of 60° with the horizontal. Given the coefficient of kinetic friction between the object and the surface is k = 0.1, and g = 10 m/s², what is the magnitude of the acceleration of the object?
1.73 m/s²
2.46 m/s²
0.173 m/s²
0.246 m/s²
A ball with a mass of 200 g traveling at a speed of 20 m/s collides perpendicularly with a wall and bounces back at a speed of 10 m/s. The collision time with the wall is Δt = 0.05 s. Calculate the force exerted by the wall on the ball.
40 N
80 N
120 N
160 N
A ball hits a wall with a speed of 10 m/s. The time of impact is 0.05 s. Calculate the force exerted by the wall on the ball.
40 N
80 N
120 N
160 N
An object with a mass of 20 kg is held stationary on an inclined plane by a string parallel to the inclined plane. Given the angle of inclination is 45 degrees, g = 10 m/s², and friction is negligible. What is the value of the tension in the string?
100 N
200 N
141 N
282 N
An object is dropped from a height H+h vertically. At the same time, a second object is thrown upwards from below with an initial speed v₀. What must the speed of both objects be for them to meet at height h?
0.5 * sqrt(2g(H+h))
0.5 * sqrt(2g(H+h))
0.5 * sqrt(2g(H+h))
0.5 * sqrt(2g(H+h))
An object is dropped from a height H+h vertically. At the same time, a second object is thrown upwards from below with an initial speed v₀. What is the distance between the two objects before they meet over time?
2 * H + h + v₀ * t - 0.5 * g * t²
H + h + v₀ * t
2 * v₀ * t - H - h + 0.5 * g * t²
v₀ * t - H - h
From the top of a building, an object is dropped. One second later, a second object is dropped from a lower floor. How long after the first object is dropped will the two objects meet?
1 s
1.5 s
2 s
2.5 s
At the same time, one object is dropped freely and another object is thrown horizontally with speed v₀ from a height h. Ignoring air resistance, what is the distance between the two objects when they hit the ground?
0.5 * (v₀² * h / g)
0.5 * (v₀² * h / g) + h
0.5 * (v₀² * h / g)
0.5 * (v₀² * h / g) + g
A truck loaded with sand has a mass of 20 kg and is moving without friction.
What is the expression given when an object touches the ground?
0 2h v g
2 0 1 2 v gh +
0 2 v gh
2 0 2 v gh g +
A truck carrying sand has a mass M = 20 kg moving without friction at a speed v1 = 1 m/s on a horizontal road. A ball with a mass m = 2 kg is moving in the opposite direction at a horizontal speed v2 = 11 m/s. After meeting the truck, the ball sinks into the sand. What is the final speed of the truck?
0.09 m/s
-0.09 m/s
1.91 m/s
-1.91 m/s
Which statement about air conditioners is incorrect?
It is a device that receives work to transfer heat from a cold source to a hot source.
Let A be the work received and Q2 be the heat taken from the cold source, then the efficiency of the air conditioner ε = Q2/A.
The efficiency of the air conditioner is always less than 1.
In a room with an air conditioner, the hot source must be outside the room, and the cold source inside the room.
Which of the following is not a characteristic of the motion of gas molecules?
Chaotic motion.
Chaotic and continuous motion.
Continuous motion.
Chaotic motion around fixed equilibrium positions.
Which quantity is not a state parameter of a gas?
Mass.
Pressure.
Volume.
Absolute temperature.
A certain amount of gas is defined by a set of three parameters consisting of
Pressure, volume, mass.
Pressure, temperature, volume.
Volume, mass, temperature.
Pressure, temperature, mass.
The change in internal energy of n moles of ideal monatomic gas from state (1) to state (2) is calculated by which of the following formulas?
ΔU = n.R.ΔT/2
ΔU = 3.n.R.ΔT/2
ΔU = 5.n.R.ΔT/2
ΔU = n.R.ΔT.i/2
Under a pressure of 10^5 Pa, a quantity of gas has a volume of 10 liters. If the temperature is kept constant and the pressure increases to 1.25 * 10^5 Pa, what is the volume of this gas?
V2 = 7 liters
V2 = 8 liters
V2 = 9 liters
V2 = 10 liters
A cylinder contains 100 cm³ of gas at a pressure of 2 * 10^5 Pa. The piston compresses the gas isothermally in the cylinder to 50 cm³. What is the pressure of the gas in the cylinder at this point?
2 * 10^5 Pa
3 * 10^5 Pa
4 * 10^5 Pa
5 * 10^5 Pa
A quantity of gas at 0°C has a pressure of 1.5 * 10^5 Pa. If the volume of the gas remains constant, what will the pressure be at 273°C?
p2 = 10^5 Pa
p2 = 2 * 10^5 Pa
p2 = 3 * 10^5 Pa
p2 = 4 * 10^5 Pa
A container holds a quantity of gas at a temperature of 27°C and a pressure of 2 * 10^5 Pa. If the pressure doubles, what will the temperature of the gas be?
T = 300 K
T = 54 K
T = 13.5 K
T = 600 K
A closed container holds oxygen gas at a temperature of 27°C and a pressure of 10^5 Pa. If the container is exposed to sunlight at a temperature of 177°C, what will the pressure in the container be?
1.5 * 10^5 Pa
2 * 10^5 Pa
2.5 * 10^5 Pa
3 * 10^5 Pa
A pump contains 100 cm³ of air at a temperature of 27°C and a pressure of 10^5 Pa. When the air is compressed to 20 cm³ and the temperature rises to 327°C, what is the pressure of the air in the pump?
p2 = 7 * 10^5 Pa
p2 = 8 * 10^5 Pa
p2 = 9 * 10^5 Pa
p2 = 10 * 10^5 Pa
What is the air pressure in the pump?
p2 = 7.10^5 Pa.
p2 = 8.10^5 Pa.
p2 = 9.10^5 Pa.
p2 = 10.10^5 Pa.
In the laboratory, 40 cm3 of oxygen gas is prepared at a pressure of 750 mmHg and a temperature of 300 K. When the pressure is 1500 mmHg and the temperature is 150K, what is the volume of that gas?
10 cm3.
20 cm3.
30 cm3.
40 cm3.
A quantity of gas is contained in a cylinder with a movable piston. The state parameters of this gas are: 2 at, 15 liters, 300 K. When the piston compresses the gas, the pressure increases to 3.5 at, and the volume decreases to 12 liters. What is the temperature of the compressed gas?
400 K.
420 K.
600 K.
150 K.
An ideal gas has a pressure of 1 at and is increased to 4 at at constant temperature, changing its volume by 3 liters. What was the initial volume of that gas?
4 liters.
8 liters.
12 liters.
16 liters.
What is an isothermal process?
Temperature is kept constant.
Volume is kept constant.
Pressure is kept constant.
The gas does not exchange heat with the outside.
Why does matter in the gaseous state (gas) not have a definite volume and shape?
Gas atoms and molecules are very far apart.
Gas atoms and molecules are very close together.
Gas atoms and molecules vibrate strongly due to heat.
Gas atoms and molecules move chaotically due to heat.
A closed container holds helium gas containing N = 1.505 x 10^23 helium atoms at 0°C and has a pressure of 1 atm. What is the volume of the container holding the gas?
5.6 liters.
11.2 liters.
22.4 liters.
28 liters.
A gas cylinder is at a temperature of 33°C under a pressure of 300 kPa. If the temperature is increased to 37°C at constant volume, what is the increase in pressure of the gas in the cylinder?
(a)
A gas cylinder is filled at a temperature of 33°C under a pressure of 300 kPa. If the temperature is increased to 37°C at constant volume, what is the increase in pressure of the gas in the cylinder?
3.92 kPa
3.24 kPa
5.64 kPa
4.32 kPa
The isochoric process is the process of state change of a gas in which:
the temperature is kept constant.
the volume is kept constant.
the pressure is kept constant.
the gas does not exchange heat with the outside.
Which of the following statements is false?
Two like charges repel each other, while opposite charges attract each other.
The charge of an isolated system remains constant.
The charge of an electron is a fundamental charge.
The force between point charges is inversely proportional to the distance between them.
How will the interaction force between two point charges change if we double the magnitude of each charge and also double the distance between them?
Double
Halve
Unchanged
Quadruple
A charge Q = -5.10^-8 C is placed in air. What is the magnitude of the electric field vector caused by charge Q at point M, which is 30 cm away from it?
15 kV/m
5 kV/m
15 V/m
5 V/m
Two point charges of the same sign q1 and q2 (q1 = 4q2) are placed at points A and B, separated by a distance of 3a in air. A point charge Q is placed on segment AB, at a distance a from B. What is the characteristic of the resultant force exerted by q1 and q2 on Q?
Always directed towards A.
Always directed towards B.
Always zero.
Directed towards A if O is opposite in sign to q1.
Which of the following statements is false?
The electric field vector is a quantity that characterizes the electric field in terms of force action.
In an isotropic dielectric medium, the electric field strength decreases by ε times.
Which of the following statements is incorrect?
The vector of electric field intensity is a quantity characteristic of the electric field in terms of force action.
In an isotropic dielectric medium, the electric field intensity decreases by ε times compared to that in a vacuum.
The unit of electric field intensity is volts per meter (V/m).
Static electric field is an electric field with constant intensity E at all points.
Which of the following statements is incorrect?
The flux of the electric field intensity vector through a surface (S) is called electric flux.
Electric flux is a scalar quantity that can be positive, negative, or zero.
The electric flux through any surface (S) is always zero.
In the SI system, the unit of electric flux is volt meter (Vm).
Which expression is used to calculate the electric flux D through a closed surface (S)?
D = ∫(q/ε) dS
D = ∫(E . dS)
D = ∫(D . dS)
D = ∑(q)
Choose the correct statement:
A steel ball on a dry wooden table, after being charged, has its charge uniformly distributed throughout the volume of the ball.
A charged object with charge distributed throughout its volume is certainly not a metal.
A hexagonal steel plate that is charged will have its charge uniformly distributed on the surface of the plate.
Metal objects, when charged, always have their charge uniformly distributed on the outer surface of the object.
In the SI system, the unit of electric field intensity is
V/m.
Vm.
C/m².
C.
In the SI system, the unit of electric inductance D is
volts per meter (V/m).
volt meter (Vm).
coulombs per square meter (C/m²).
coulomb (C).
A charged conductor will have its charge distributed
evenly throughout the entire volume of the conductor.
evenly on the surface of the conductor.
only inside the conductor.
only on the surface of the conductor, depending on the shape of the surface.
What is the distribution of charge in a conductor?
Evenly throughout the entire volume of the conductor.
Evenly on the surface of the conductor.
Only inside the conductor.
Only on the surface of the conductor, depending on the shape of the surface.
When two point charges q1 and q2 are placed close to each other, they repel each other. Which conclusion is incorrect?
q1 and q2 are both positive charges.
q1 and q2 are both negative charges.
q1 and q2 have opposite signs.
q1 and q2 have the same sign.
Which statement is incorrect regarding the interaction force between two point charges in a vacuum?
The direction is along the straight line connecting the two charges.
The magnitude is directly proportional to the product of the magnitudes of the two charges.
The magnitude is inversely proportional to the distance between the two charges.
It is an attractive force when the two charges have opposite signs.
According to electron theory, which concept about charged objects is correct?
A positively charged object only has positive charges.
A negatively charged object only has negative charges.
A positively charged object lacks electrons, while a negatively charged object has excess electrons.
A charged object can be positive or negative depending on the number of electrons in the atom.
The graph representing the Coulomb interaction force between two charges in relation to the square of the distance between them is a line that is
Hyperbolic.
Straight.
Parabolic.
Elliptical.
When two point charges are separated by a distance r in air, they attract each other with a force F. If they are placed in oil with a dielectric constant ε = 4 and separated by a distance r' = r/2, what is the force of attraction between them?
F.
F/2.
2F.
4F.
Two metallic spheres carrying charges q1 and q2 touch each other. After that, they are separated, and each sphere carries a charge q which is
q = q1 + q2.
q = q1 - q2.
q = (q1 + q2)/2.
q = (q1 - q2)/2.
Two light spheres of equal mass are suspended close to each other by two strings.
Two light spheres of equal mass are suspended close to each other by two insulating strings of equal length and the two spheres do not touch each other. If both spheres are charged with the same sign but have different magnitudes, the force acting makes the two strings deviate at angles with respect to the vertical.
Equal.
The sphere with the larger charge has a larger deviation angle.
The sphere with the larger charge has a smaller deviation angle.
The sphere with the smaller charge has a smaller deviation angle.
Object A is electrically neutral and is brought into contact with object B which is positively charged, then object A also becomes positively charged because
Positive charge from object B moves to object A.
Negative ions from object A move to object B.
Electrons move from object A to object B.
Electrons move from object B to object A.
Charging a plastic rod and bringing it close to two objects M and N, we see that the plastic rod attracts both objects M and N. Which of the following situations certainly does not occur?
M and N are charged with the same sign.
M and N are both uncharged.
M is charged, while N is uncharged.
M and N are charged with opposite signs.
If the magnitude of the charge of one of the two charged objects is reduced by half, while the distance between them is doubled, then the electric interaction force between the two objects will be.
Reduced by 2 times.
Reduced by 4 times.
Reduced by 8 times.
Unchanged.
What is the correct answer when talking about the relationship between the electric field intensity vector and the electric force?
E is in the same direction as F acting on a test charge placed in that electric field.
E is in the opposite direction to F acting on a test charge placed in that electric field.
E is in the same direction as F acting on a surplus test charge.
Two small metal spheres of the same size have charges q1 = 5 μC and q2 = -3 μC. After they touch each other and are then placed 5 cm apart in a vacuum, what is the interaction force between the two point charges?
4.1 N
5.2 N
3.6 N
1.7 N
There are three metal spheres of the same size. Sphere A has a charge of 27 μC, sphere B has a charge of -3 μC, and sphere C has no charge. When spheres A and B touch and are then separated, and then spheres B and C touch, what are the charges on each sphere?
qA = 6 μC, qB = qC = 12 μC
qA = 12 μC, qB = qC = 6 μC
qA = qB = 6 μC, qC = 12 μC
qA = qB = 12 μC, qC = 6 μC
At the three vertices A, B, C of an equilateral triangle with a side length of 15 cm, there are point charges qA = +2 μC, qB = 8 μC, and qC = -8 μC. What is the magnitude of the vector force acting on qA?
F = 6.4 N parallel to BC, directed from B to C
F = 8.4 N perpendicular to BC
F = 5.9 N parallel to BC, directed from C to B
F = 6.4 N along AB
Four point charges q1, q2, q3, q4 are placed at the vertices of a square ABCD in the air. Knowing that the resultant force acting on q4 at D is along AD, what is the relationship between the charges q2 and q3?
q2 = 2q3
q2 = 22 - q3
q2 = (2 + 1)q3
q2 = (2 - 1)q3
Two point charges q1 = 2.10^-8 C and q2 = -1.8.10^-7 C are placed at points A and B, respectively, which are 12 cm apart in the air. What is the force between them?
Two point charges q1 = 2.10^-8 C; q2 = -1.8.10^-7 C are placed at points A and B, 12 cm apart in air. Place a charge q3 at point C. Find the position, sign, and magnitude of q3 for the system of three charges q1, q2, q3 to be in equilibrium?
q3 = -4.5.10^-8 C; CA = 6 cm; CB = 18 cm
q3 = 4.5.10^-8 C; CA = 6 cm; CB = 18 cm
q3 = -4.5.10^-8 C; CA = 3 cm; CB = 9 cm
q3 = 4.5.10^-8 C; CA = 3 cm; CB = 9 cm
A point charge q < 0 is placed on the axis of a positively charged ring centered at O (as shown in the figure), and then released. Which of the following conclusions is correct?
Charge q moves towards the ring, stops at point O.
Charge q accelerates towards the ring, stops at point O, then continues moving straight, slowing down, and eventually reverses direction.
Charge q remains stationary at M.
Charge q moves away from point M towards the center O.
A very large flat metal sheet (P) is uniformly charged. Compare the electric field strength caused by (P) at points A, B, C (as shown in the figure).
EA > EB > EC.
EA < EB < EC.
EA = EB = EC.
EA + EC = 2EB.
A circular wire loop with radius R is uniformly charged with a total charge Q, placed in air. What is the expression for the electric field strength at point M on the axis of the loop, at a distance R from the center of the loop?
ER = 2k |Q| / R^2
ER = 2k |Q| / 2R
ER = 2k |Q| / 2R^2
E = 0
In a vacuum, at the 6 vertices of a regular hexagon with side a, 6 point charges of equal magnitude q are placed, consisting of 3 negative and 3 positive charges alternately (k = 9.10^9 Nm^2/C^2). What is the electric field strength at the center O of that hexagon?
EA = 2kq / a
EA = 2 * 6kq / a
EA = 2 * 3kq / a
E = 0
What is the electric field intensity at point O of the hexagon with one negative charge and three positive charges?
2kq/Ea
2/6kq/Ea
2/3kq/Ea
E = 0
What is the expression for the electric field intensity caused by an infinitely long charged wire at point M, which is a distance h from the wire?
k |E| = λ/h
2k |E| = λ/h
2k |E| = λ/h
k |E| = λ/2h
What is the electric field intensity caused by an infinite plane with a uniform surface charge density σ = 17.7 x 10^-10 C/m² at point M, which is a distance a = 10 cm from the plane?
100 V/m
10 V/m
1000 V/m
200 V/m
If two point charges q and 4q are placed at points A and B, 30 cm apart, how far from A should a test charge be placed at point M on segment AB for it to remain stationary?
7.5 cm
10 cm
20 cm
22.5 cm
If two equal but opposite point charges q1 and q2 are placed on a straight line, and an additional point charge Q < 0 is placed on the line, what is the direction of the force acting on Q?
Towards x, if Q is placed on segment x - q1.
Towards y, if Q is placed on segment q2 - y.
Towards q1, if Q is placed on segment q1 - q2.
Zero, if Q is placed at the midpoint of segment q1 - q2.
What is the electric flux through surface (S) caused by two point charges Q1 = 8 μC and Q2 = -5 μC placed in air and outside the closed surface?
3 x 10^-6 (Vm)
3.4 x 10^5 (Vm)
0 (Vm)
9 x 10^5 (Vm)
What is the path of electric field lines?
Perpendicular to the electric field vector E at that point.
Tangent to it at that point.
The electric field line is a line that is perpendicular to the electric field intensity vector at that point.
Perpendicular to the electric field intensity vector
Tangent to it at each point coinciding with the direction of the electric field intensity vector
Normal to it at each point coinciding with the direction of the electric field intensity vector
Drawn by magnetic particles.
For a negatively charged sphere with charge Q < 0, which statement is FALSE?
The charge is not distributed inside the sphere.
Inside the sphere, the electric field intensity is zero.
The charge is uniformly distributed on the surface of the sphere.
The potential at the center O is greater than at the surface of the sphere.
Two charges q1 and q2 are placed 6 cm apart in air, and the interaction force between them is 2.10^-5 N. When placed 3 cm apart in oil with a dielectric constant ε = 2, what is the interaction force between them?
4.10^-5 N
10^-5 N
0.5.10^-5 N
6.10^-5 N
Two capacitors C1 = 10 μF and C2 = 20 μF can withstand maximum voltages U1 = 150 V and U2 = 200 V respectively. If these capacitors are connected in series, what is the maximum voltage the capacitor bank can withstand?
350 V
225 V
175 V
200 V
Two charges q1 = +q and q2 = -q are placed at points A and B in air, with AB = 2a. What is the magnitude of the electric field intensity at point M on the perpendicular bisector of AB, at a distance h from AB?
22kq/(2ha^2)
(2kq)/(2ha^2)
(3kq)/(2ha^2)
22kq/(2ha^2)
Two horizontal metal plates with opposite charges are placed in oil, creating a uniform electric field directed downwards with an intensity of 20000 V/m. A steel ball with a radius of 1 cm and charge q is suspended in the space between the two plates. Knowing the specific gravity of the ball...
A spherical iron ball with a radius of 1 cm carries a charge q suspended in the space between two metal plates. The intensity is 20000 V/m. The density of iron is 7800 kg/m³, and the density of oil is 800 kg/m³. What is the value of charge q?
- 12.7 μC
14.7 μC
- 14.7 μC
12.7 μC
Three point charges q1, q2 = -12.5 × 10^-8 C, q3 are placed at points A, B, C of a rectangle ABCD with sides AD = a = 3 cm, AB = b = 4 cm. The resultant electric field at point D is zero. What are the values of charges q1 and q3?
q1 = 2.7 × 10^-8 C; q3 = 6.4 × 10^-8 C
q1 = -2.7 × 10^-8 C; q3 = -6.4 × 10^-8 C
q1 = 5.7 × 10^-8 C; q3 = 3.4 × 10^-8 C
q1 = -5.7 × 10^-8 C; q3 = -3.4 × 10^-8 C
At two points A and B in the air, two point charges qA = qB = 3 × 10^-7 C are placed, with AB = 12 cm. Point M is located on the perpendicular bisector of AB, 8 cm away from segment AB. What is the magnitude of the resultant electric field caused by qA and qB?
4.32 × 10^5 V/m and perpendicular to AB
4.32 × 10^5 V/m and parallel to AB
1.35 × 10^5 V/m and perpendicular to AB
1.35 × 10^5 V/m and parallel to AB
At two vertices M and P of a square MNPQ with side a, two point charges qM = qP = -3 × 10^-6 C are placed. What charge q should be placed at vertex Q so that the electric field caused by the three charges at point N is neutralized?
q = 6 × 10^-6 C
q = -6 × 10^-6 C
q = -3 × 10^-6 C
q = 3 × 10^-6 C
Given three point charges q1 = q2 = q3 = q = 6 μC placed at the vertices of an equilateral triangle ABC with side a = 10 cm (in vacuum). Calculate the force acting on charge q1. (k = 9 × 10^9 Nm²/C²)
F = 64.8 N
F = 56.1 N
F = 28.1 N
F = 0 N
Calculate the force acting on the charge q1. (k = 9.10^9 Nm^2/C^2):
64.8 N
56.1 N
28.1 N
32.4 N
Calculate the magnitude of the electric field vector caused by two point charges Q1 = 8 μC, Q2 = -6 μC placed at points A and B, 10 cm apart, at point M, where MA = 8 cm and MB = 6 cm.
18.75 x 10^6 V/m
7.2 x 10^6 V/m
5.85 x 10^6 V/m
6.48 x 10^6 V/m
A parallel plate capacitor is fixed with a battery. If the two plates move closer together, which statement is FALSE?
The electric field strength inside the capacitor increases.
The energy of the capacitor remains constant.
The voltage between the two plates remains constant.
The capacitance of the capacitor increases.
Calculate the electric flux Φ through a spherical surface centered at B with radius R = 10 cm, given two point charges qA = -5 x 10^-9 C and qB = 5 x 10^-9 C placed 20 cm apart.
5 x 10^-9 (Vm)
565 (Vm)
4.4 x 10^-20 (Vm)
0 (Vm)
Find the electric potential at the center of a metal sphere with radius 50 cm, charged with Q = 5 x 10^-6 C, choosing the reference potential at infinity.
V = 9 x 10^4 (V)
V = 1.8 x 10^5 (V)
V = 300 (V)
V = 0 (V)
For a solid metal sphere of radius R, carrying a positive charge Q, what expressions describe the electric field E and potential V at point P located at a distance r > R from the center O? (Reference potential at infinity, k = 9.10^9 Nm^2/C^2, ε is the dielectric constant).
E_P = 2kQ/rε and V_P = kQ/rε
E_P = 2kQ/rε and V_P = kQ/Rε
E_P = 2kQ/Rε and V_P = kQ/Rε
E_P = 0 and V_P = 0
Two point charges both equal to +q are placed 5 cm apart. If one charge is replaced with -q, what happens to the interaction force?
Two point charges both equal to +q are placed 5 cm apart. If one charge is replaced by -q, to keep the interaction force unchanged, what should be the distance between them?
2.5 cm
5 cm
10 cm
20 cm
Two equal charges placed in air 4 cm apart exert a repulsive force of 10^-5 N. To make the attractive force between them 2.5 * 10^-6 N, what should be the distance between them?
1 cm
8 cm
16 cm
2 cm
Two point charges q1 = 10^-9 C and q2 = -2 * 10^-9 C attract each other with a force of 10^-5 N when placed in air. What is the distance between them?
3 cm
4 cm
4.24 cm
5.65 cm
For a system of three isolated charges q1, q2, q3 lying on the same straight line, if q1 and q3 are positive charges 60 cm apart and q1 = 4q3, the force on q2 is zero. Where should q2 be placed?
20 cm from q1, 80 cm from q3
20 cm from q1, 40 cm from q3
40 cm from q1, 20 cm from q3
80 cm from q1, 20 cm from q3
The electric field strength of a point charge at A is 36 V/m and at B is 9 V/m. What is the electric field strength at the midpoint C of AB, knowing that A and B lie on the same field line?
30 V/m
25 V/m
16 V/m
12 V/m
A positive point charge q, with mass m, initially at rest, is released into a uniform electric field E directed along the positive x-axis (ignoring gravity and drag). What is the nature of the motion of q?
Uniformly accelerated motion in the positive x-direction with acceleration a = qE/m
Uniformly accelerated motion in the negative x-direction with acceleration a = qE/m
Uniform motion in the positive x-direction
Uniform motion in the negative x-direction
What is the acceleration of the object moving in the positive direction of the Ox axis?
Accelerating uniformly in the positive direction of the Ox axis.
Accelerating uniformly in the negative direction of the Ox axis.
Moving uniformly in the positive direction of the Ox axis.
Moving uniformly in the negative direction of the Ox axis.
Compare the electric field intensity caused by the flat metal sheet (P) at points A, B, C.
E_A > E_B > E_C
E_A = E_B = E_C
E_A = E_B < E_C
E_A = E_B > E_C
What expression determines the electric field vector caused by point charge Q at point M?
E = (Q / (4 * π * ε * r^2)) * e_r
E = (q / (4 * π * ε * r^2)) * e_r
E = (Q * q / (4 * π * ε * r^2)) * e_r
E = (Q / (4 * π * ε * r^3)) * e_r
What is the expression for the electric field intensity at the center of a uniformly charged circular loop with radius R?
E = (2 * k * |Q|) / R
E = (2 * k * |Q|) / (2 * R)
E = (2 * k * |Q|) / (2 * R^2)
E = 0
When an electron enters a magnetic field along the lines of magnetic force, what happens?
The motion of the electron continues unchanged.
The direction of the electron's motion changes.
The velocity of the electron changes.
The energy of the electron changes.
A proton moves uniformly in a region with a uniform magnetic field and electric field. In the Cartesian coordinate system Oxyz, if the proton moves along...
