PHYSCI Physical Science
Task:
Multiple Choice –
Highlight the correct answer in yellow.
1.The weight of a 60-kg person is
A. 6.1 N.
B. 60 N.
C. 69.8 N.
D. 588 N.
2. A 3000-kg truck accelerates from 10 m/s to 30 m/s in 8 s. The net force on the truck is
A. 765 N.
B. 7500 N.
C. 11,250 N.
D. 15,000 N.
3. The braking force needed to bring a 4000-kg truck to a stop from a speed of 20 m/s in 5 s is
A. 1000 N.
B 1633 N.
C 9800 N.
D. 16,000 N.
4. The weight of an object
A. is the same everywhere in the universe.
B. depends only upon its mass.
C. depends only upon the acceleration of gravity.
D. depends upon both its mass and the acceleration of gravity.
5. According to Newton’s third law of motion,
A. there is no such thing as a single force acting on an object.
B. for every force there is an equal and opposite reaction force, but each acts on a different object.
C. action and reaction forces need not be equal, but must act in opposite directions.
D. action and reaction forces must be equal, but need not act in opposite directions
6. Angular momentum is conserved in the absence of which of the following?
A. a net torque B. linear momentum C. gravity D. inertia
7. A net force _________.
A. can produce motion B. is a scalar quantity C. is capable of producing a change in velocity
D. both (a) and (c)
8. When a toy floats in a swimming pool, the buoyant force exerted on the toy depends on the volume of ________?
A. water in the pool
B. the pool
C. the water displaced
D. the toy under water
9. What is necessary for a change in velocity?
A. an unbalanced force
B. inertia
C. a change in direction
D. a zero net force
10. Which of the following units represent angular momentum?
A. B. C. D.
Decide whether each statement is true or false.
11. A force always produces motion.
12. Galileo concluded that objects could not remain in motion without a net force.
13. The coefficient of static friction is greater than the coefficient of kinetic friction.
14. It takes less force to get an object moving than it does to keep it moving.
15. In a free space with negligible gravity an object would travel indefinitely.
Fill in the Blank
16. An object will be in ______________ at any submerged depth in a fluid if the average density of the object and the density of the fluid are __________.
17. The newton unit of force is equal to ____________ in standard units.
18. The angular momentum of an object is not conserved if the object is acted upon by unbalanced _______________.
19. __________ __________ occurs when there is relative sliding motion between the surfaces in contact.
20. _________ is related to gravitational force acting on a mass or object.
Matching
21. _________ buoyant force
a. gives the magnitude of the buoyant force
b. capable of producing motion or a change in
22. _________ Gravitation motion
c. occurs in the absence of an unbalanced force
23. _________ Archimedes’ principle
d. keeps the Moon in orbit around the Earth
24. _________ Law of inertia
e. required for an object to float
25. _________ Newton’s second law of motion
26.Distinguish between mass and weight. Explain why the weight of a body changes while mass always stays the same everywhere.
27.Describe the relationship between (a) force and acceleration, and (b) mass and acceleration.
28.A 1200 kg car goes from 13 m/s to 25 m/s in 16 s. What is the average force acting upon it?
29.Find the braking force needed to bring a 3500-kg truck to a stop from a speed of 18 m/s in 7 s.
30.What centripetal force is needed to keep a 1-kg ball moving in a circle of radius 2 m at a speed of 5 m/s?
31.A1500-kg car is traveling at 18 m/s on a road such that the maximum frictional force between its tires and the road is 10000 N. Find the minimum turning radius of the car.
32.A 2500-kg truck accelerates from 22 m/s to 40 m/s in 6 s. Calculate the net force on the truck.
33.Calculate the linear momentum of a pick-up truck that has a mass of 1000 kg and is traveling eastward at 20 m/s.
34. Determine the weight on the Moon of a person whose weight on the Earth is 180 lb.
35. A child’s cubic play block has a mass of 120 g and sides of 5.00 cm. When placed in the bathtub full of water, will the cube sink or float? (Hint: Find density of cube and refer to Chapter 1.6)