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1.Which of the following is an example of work?

A.Tim worked hard to carry a box of books across a room
B.A scientist works in the laboratory
C.Sam and Rachel worked hard to push the car but it did not move
D.Joann did work on a box when she pulled it across the floor

2.Joe carries his 5 kg cat 3 m horizontally across the living room. What is the net work done on the cat?
A. 0J
B. 15J
C. 150J
D. 180J

3.Which of the following is associated with an object in motion?
A.potential energy
B.nonmechanical energy
C.kinetic energy
D.elastic potential energy

4.Which of the following is associated with an object due to its position?
A.potential energy
B.positional energy
C.total energy
D.kinetic energy

5.What is kinetic energy of a 1000 kg truck moving at 32.0 m/s? *
A.1.2 x 10⁵ J
B.3.21 x 10⁵ J
C.5.12 x 10⁵ J
D.6.34 x 10⁵ J

2 Answers

4 votes
hope this helps i might be incorrect on one of them

1-a
2-d
3-d
4-b
5-c
User Fazo
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6.9k points
4 votes
1. Using the Physics definition of work, Joann is the only one who does any. (D)

2. No work is done during horizontal motion, because gravity doesn't act in that direction. (A)

3. The energy associated with motion is called kinetic energy. (C)

4. The energy associated with vertical position is called potential energy. (A)

5. Kinetic energy of a moving object is (1/2) (mass) (speed)² .

For the truck, it's

(1/2) (1000 kg) (32 m/s)²

= (500 kg) (1024 m²/s²)

= 512,000 kg-m²/s²

= 512,000 joules (C)