An insect jumps with an initial vertical velocity of 1.0 m/s, reaching a maximum height of 3.5 × 10^–2 m. Assume the deceleration is uniform. What is the magnitude of the deceleration?
A 3.6 m s^–2
B 9.8 m s^–2
C 14 m s^–2
D 29 m s^–2
A body having uniform acceleration a increases its velocity from u to v in time t. Which expression would not give a correct value for the body’s displacement during time t ?
A sprinter runs a 100 m race in a straight line. He accelerates from the starting block at a constant acceleration of 2.5 m s^–2 to reach his maximum speed of 10 m s^–1. He maintains this speed until he crosses the finish line.
Which time does it take the sprinter to run the race?
A 4 s
B 10 s
C 12 s
D 20 s
The acceleration of free fall on the Moon is one-sixth of that on Earth. On Earth it takes time t for a stone to fall from rest a distance of 2 m.
What is the time taken for a stone to fall from rest a distance of 2 m on the Moon?
In an experiment to determine the acceleration of free fall g, a ball-bearing is held by an electromagnet. When the current to the electromagnet is switched off, a clock starts and the ball- bearing falls. After falling a distance h, the ball-bearing strikes a switch to stop the clock which measures the time t of the fall.
Which expression can be used to calculate the value of g ?
An object is thrown with velocity 5.2 m s^–1 vertically upwards on the Moon. The acceleration due to gravity on the Moon is 1.62 m s^–2. What is the time taken for the object to return to its starting point?
A 2.5 s
B 3.2 s
C 4.5 s
D 6.4 s
An experiment is performed to measure the acceleration of free fall g. A body falls between two fixed points. The four measurements shown below are taken.
Which measurement is not required for the calculation of g ?
A the distance fallen by the body
B the initial velocity of the body
C the mass of the body
D the time taken for the body to fall
An aeroplane travels at an average speed of 600 km h–1 on an outward flight and at 400 km h^–1 on the return flight over the same distance.
What is the average speed of the whole flight?
A 111 m s^–1
B 167 m s^–1
C 480 km h^–1
D 500 km h^–1
On a particular railway, a train driver applies the brake of the train at a yellow signal, a distance of1.0 km from a red signal, where the train stops. The maximum deceleration of the train is 0.20 m s^–2. Assuming uniform deceleration, what is the maximum safe speed of the train at the yellow signal?
A 14 m s^–1
B 20 m s^–1
C 40 m s^–1
D 400 m s^–1
A person, travelling on a motorway a total distance of 200 km, travels the first 90 km at anaverage speed of 80 km h^–1. Which average speed must be obtained for the rest of the journey if the person is to reach the destination in a total time of 2 hours 0 minutes?
A 110 km h^–1
B 120 km h^–1
C 122 km h^–1
D 126 km h^–1
A cannon fires a cannonball with an initial speed v at an angle α to the horizontal. Which equation is correct for the maximum height H reached?
A golf ball is hit with the same force and direction on the Earth and on the Moon. Which diagram best represents the shapes of the paths taken by the golf ball?
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