A Level MC Review 1

Which of the following expresses the joule in base units?

• kgms⁻¹

• kgms⁻²

• kgm² s⁻¹

• kgm² s⁻²

Select the graph that correctly shows the variation of an object’s kinetic energy E_k with its velocity v

• A

• B

• C

• D

A block of mass m is placed on a bench and a horizontal force F is applied to the block. The block accelerates along the bench, travels a distance d in time t and reaches a velocity v.

The work done by the force F on the block is

• Fd

• Ft

• Fv

• mgh

To travel from position A to position B, a car drives 20 km due east and then 20 km due south.

Select the row from the table that correctly expresses the magnitudes of the total distance travelled and the total displacement of the car at the end of this journey.

• A

• B

• C

• D

Two groups of students were asked to perform an experiment to determine the acceleration of free-fall. Each group repeated their experiment three times to check their results. In each experiment a steel ball fell through a height of just under 1m and the time for the ball to fall was measured.

Group 1 used a stopwatch to measure the time. Group 2 used light gates connected to a data logger to measure the time.

The students measured the height the ball fell using a metre rule with mm markings. The height should be recorded as

• 85cm

• 0.85m

• 0.850m

• 8.5 × 10⁻¹m

Two groups of students were asked to perform an experiment to determine the acceleration of free-fall. Each group repeated their experiment three times to check their results. In each experiment a steel ball fell through a height of just under 1m and the time for the ball to fall was measured.

Group 1 used a stopwatch to measure the time. Group 2 used light gates connected to a data logger to measure the time. Select the row from the table that correctly describes the reliability and validity of the results obtained for each group.

• A

• B

• C

• D

An object of volume 2.4×10−5m³ was suspended from a spring balance in air and its weight, in newtons, was read from the scale. The object was then placed in a measuring cylinder containing water of density 1000kgm^−3.

The reading on the spring balance

• decreased by (2.4×10⁻⁵)×(1000)

• decreased by (2.4×10⁻⁵)×(1000)×(9.81)

• increased by (2.4×10⁻⁵)×(1000)

• increased by (2.4×10⁻⁵)×(1000)×(9.81)

A uniform rod is found to balance when a pivot is placed at the midpoint as shown. The rod is replaced with one made from two different materials. The right-hand half of the new rod has double the density but half the diameter of the left-hand half of the rod. Where should the pivot be placed in order to balance the replacement rod?

• at O

• to the left of O

• to the right of O

• there is no balance point

Concrete is used in both the spans and the supporting columns in a bridge. The spans need to be reinforced with steel but the supporting columns do not.

This is because concrete is

• strong under both tension and compression.

• strong under tension and weak under compression.

• weak under both tension and compression.

• weak under tension and strong under compression.

A 1.8 kg mass is suspended from the end of a spring of original length 0.040m. The spring extends and is now three times its original length. The work done on the spring is

• 0.072J

• 0.11 J

• 0.71J

• 1.1J