Untitled Quiz

If two balls were thrown horizontally from the same height but at different velocities, they would have the same acceleration and hit the ground at the same time.

• True

• False

Answer explanation

Remember, height affects time but they are dropped from the SAME height.

Initial velocity only affects distance/range.

Acceleration is the same for both objects.

10 m/s2

Drag the correct answers for the position - time graph.

Speed is ​ ​ (a)   and forces are​ (b)   .

• increasing
• unbalanced
• decreasing
• constant
• balanced

Tags

NGSS.MS-PS3-1

A group of students are told to measure the acceleration of the Atwood machine pictured above. One student suggests that they use a 2 kg and 4 kg mass instead. On their second trial, they change the mass to 5 and 7. How will the acceleration of the second trial compare to the first trial?

• greater

• less

• equal

Answer explanation

Remember: More mass added to the system will cause it to accelerate less. It will move slower because it is heavier.

Tags

NGSS.MS-PS2-2

An object slides to the right across a horizontal surface such that it slows down due to the force of friction that is exerted on the object.

Draw the FBD of the object.

Answer explanation

Normal Force and Gravitation Force are equal because the object is not accelerating up or down. THese arrows must be equal length.

Friction must be directed to the left since the object is moving to the right.

Tags

NGSS.MS-PS2-2

The box is stationary on the ramp.

Draw the FBD that best represents the direction of forces acting on the box.

Answer explanation

Gravity must be drawn straight down.

Normal force must be at angle since it is on an inclined plane.

Friction is drawn in the opposite direction of the object moving.

Tags

NGSS.HS-PS2-1

The box is SLIDING UP the incline.

Draw the FBD that best represents the directions of forces acting on the box.

Answer explanation

Fg - must be pointing down.

Fn - must be directed up at an angle.

Ff - will pointing to the LEFT since the box is sliding up.

Fa - applied force will be directed up the incline since the object is sliding up.

Tags

NGSS.HS-PS2-1

A car is going around in circles in a clockwise direction with a constant speed.

In the circle, draw the point in which the car's velocity is directed to the left?

Use vectors to show direction.

Answer explanation

The arrow should be drawn at the bottom of the circle.

A car is going around in circles in a clockwise direction with a constant speed.

In the circle, draw the point in which the car's ACCELERATION is directed to the left?

Use vectors to show direction.

Answer explanation

Remember that centripetal acceleration is directed towards the center of the circle.

Acceleration and velocity are always perpendicular to each other.

Tags

NGSS.MS-PS2-2

What is the formula to calculate force using Newton's second law?

• F = ma

• F = mv

• F = m/a

• F = a/m

Tags

NGSS.MS-PS2-2

What is the formula to calculate acceleration using Newton's second law?

• a = F/m

• F = ma

• m = F/a

• F = m/a

Tags

NGSS.MS-PS2-2