PHYSICS QUIZ 2.1

Each of the four identical carts shown above is loaded with a total mass of 4 kilograms. All of the carts are initially at rest on the same level surface. Forces of the same magnitude directed to the right act on each of the carts for the same length of time. If friction and air resistance are negligible, which cart will have the greatest velocity when the forces cease to act?

• Cart 1

• Cart 2

• Cart 3

• Cart 4

• All carts have the same velocity

A block is pulled along a horizontal surface with a constant horizontal force of magnitude F. The surface exerts a frictional force of constant magnitude f on the block. The graph of speed V as a function of time t for the block is shown above.

If, instead, the block slides without friction but is pulled with the same horizontal force of magnitude F, which of the following would be a possible new graph of speed V as a function of time t? (The dashed line represents the old graph.)

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• 
• 
• 
• 

When a vector of magnitude 6 units is added to a vector of magnitude 8 units, the magnitude of the resultant vector will be

• Exactly 2 units

• Exactly 10 units

• Exactly 14 units

• 0 units, 10 units, or some value between them

• 2 units, 14 units, or some value between them

A 5-kilogram block is suspended by a cord from the ceiling, as shown above. The force exerted on the block by the cord is most nearly

• ON

• 25N

• 50N

• 100N

• 200N

What is the tension in the upper string of the system made up of two blocks of metal each of mass 5 kg, suspended from the ceiling by strings of negligible mass, as shown above? (g=9.8kg/m³)

• 49N

• 25N

• 980N

• 98N

• 10N

The graph of the velocity against the time of a moving object is shown below. What is the displacement between t = 3 and t = 5?

• 4m

• 2m

• equal or close to zero

• -4m

• -2m

1. This question relates to the velocity time graph shown below. Select the answer that is most representative of the physical quantity named.

At which point on the graph is no net force applied?

• A

• B

• C

• D

• E

A 400N box is suspended motionless from a steel frame by two ropes, A and B, which hang straight up and down. Which of the following statements about the tension in the two ropes is correct?

• The tension in rope A is larger than in rope B

• The tension in rope B is larger than in rope A.

• The tension in rope B is equal to rope A and equal to 200N.

• The tension in rope B is equal to rope A and less than 400N.

• The tension in rope B is equal to rope A and more than 400N.

A pile of 11 books weighing 2 N each is sitting on a table. What is the normal force acting on the books?

• 2N

• 11N

• 22N

• 33N

• 44N

Sir Isaac Newton's third law of motion is called the action-reaction law. Which of the following statements appropriately describes the action-reaction forces?

• They act on different objects

• They act on the same object.

• They are unequal in magnitude

• They act at right angles to one another.

• They act in the same direction.