1 markAn object is falling at terminal velocity.
Which of the following is not a valid conclusion from this statement?
The acceleration of the object is zero.
There is a resistive force acting on the object.
There is a resultant force acting on the object.
The object has weight.
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1 markTwo spheres approach each other along the same straight line. Their speeds are u1 and u2 before collision, and v1 and v2 after collision, in the directions shown below
Which equation is correct if the collision is perfectly elastic?
u1 – u2 = v2 + v1
u1 – u2 = v2 – v1
u1 + u2 = v2 – v1
u1 + u2 = v2 + v1
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A car has a horizontal driving force of 8.0 kN acting on it and a resistive force a quarter of this size. It has a forward horizontal acceleration of 9.2 m s–2.
What is the mass of the car?
870 kg
650 kg
1250 kg
700 kg
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1 markA bus is travelling forward at constant speed when a car collides with the bus perpendicularly to its direction of motion.
What is the effect of this force on the forward speed and sideways speed of this bus?
The forward speed increases and sideways speed increases
The forward speed decreases and sideways speed increases
The forward speed is unchanged and sideways speed increases
The forward speed decreases and sideways speed is unchanged
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