PHYSICS 9

1.  A change in the position of the object is _________.

• A. Speed

• B. Vector quantity

• C. Speed motion

• D. Motion

Answer explanation

A change in the position of the object is referred to as motion, making option D the correct choice.

2. 2.Two marbles of equal mass are rolling towards each other. One is rolling at 7 m/sec and the other at 10 m/sec. The one rolling faster has a________ momentum and ________ impulse. It will surely knock the other one backwards.

• A. lesser, lesser

• B. lesser, greater

• C. greater, lesser

• D. greater, greater

Answer explanation

The correct choice is D. The marble rolling faster has greater momentum and impulse, ensuring it knocks the other one backwards.

The quantity that has both magnitude and direction

• A. Instanteneous speed

• B. Distance

• C. Velocity

• D. Displacement

Answer explanation

Velocity is the quantity that has both magnitude and direction, making it the correct choice in this scenario.

4. 4.if the  object is at rest what kind of energy is referred to?

• a.potential energy

• b. kinetic energy 

• c. mechanical energy

• d. chemical energy

Answer explanation

When an object is at rest, it possesses potential energy, which is energy stored in an object due to its position or state.

5. A picture frame falls off the wall. Considering the presence of air, how does the kinetic energy (K) just before striking the floor compare to the potential energy (P) at its hanging point?

• A. K is equal to P.

• B. K is greater than P.

• C. K is less than P.

• D. It is impossible to tell.

Answer explanation

The kinetic energy (K) just before striking the floor is greater than the potential energy (P) at its hanging point due to the conversion of potential energy to kinetic energy as the frame falls.

6. An object that moves in dimensions and forms a curved path and is acted upon by gravity.

• a.projectile motion

• b. trajectile motion

• c.laws motion

• d. motion

Answer explanation

Projectile motion involves an object moving in dimensions, forming a curved path, and being influenced by gravity, making it the correct choice.

1. 7.Whatever the initial momentum should be _____to the final momentum

• 1. a.decrease

• 1. b.increase. 

• 1. c.reduced

• d.equal

Answer explanation

The correct choice is d. 'equal' because momentum is conserved in a closed system, so the initial momentum should be equal to the final momentum.

1. 8.From a rest bus accelerated at 

30 m/s² for 40s. What is the position of the bus at the end of 30 seconds?

• A. 116 m

• B. 1615 m

• C. 1562 m

• D. 1651 m

Answer explanation

The position of the bus at the end of 30 seconds can be calculated using the formula: position = 0.5 * acceleration * time^2. Substituting the values, we get position = 0.5 * 30 * 30^2 = 1615 m. Therefore, the correct choice is B. 1615 m.

9..  Which of the following statements describes momentum?

• A. It is the product of the body's mass and velocity.

• B.  It is the product of the body's mass and acceleration.

• C.  It is the sum of the body's mass and velocity.

• D.  It is the sum of body’s mass and acceleration

Answer explanation

Momentum is the product of the body's mass and velocity, making option A the correct choice.

10.What type of quantity are momentum and velocity?

• A. direction

•  B. scalar

• C. reactor

• D. vector

Answer explanation

Momentum and velocity are vector quantities because they have both magnitude and direction.