✓✗Assertion: The average speed of a body over a time interval can be greater than the magnitude of its average velocity.
Reason: Path length is always greater than or equal to the magnitude of displacement.

✓✗A body moves along x with velocity v = 10 m/s for 3 s, then with v = −5 m/s for 4 s. From its velocity-time graph, the net displacement is

✓✗Two cars move in the same direction with speeds 72 km/h and 54 km/h, 50 m apart. The faster car is behind. How long does it take to cover the gap and get 50 m ahead of the slower car?

✓✗A motorist drives 20 km at 40 km/h and then a further 30 km at 60 km/h in the same direction. His average speed is

✓✗In the previous question (A from rest at 2 m s⁻², B at a constant 20 m/s), the maximum separation between the cars before A catches B is

✓✗A particle has velocity \( v = 4 - 2t \) m/s. The distance it covers between t = 0 and t = 3 s is

✓✗The SI unit of acceleration is

✓✗Two parallel rail tracks run north-south. Train A moves north at 54 km/h and train B moves south at 90 km/h. The velocity of B relative to A is

✓✗For a body starting from rest with uniform acceleration, the position-time graph is

✓✗A particle is moving along the x-axis with its position (x) varying with time (t) as \( x = \alpha t^4 + \beta t^2 + \gamma t + \delta \). The ratio of its initial velocity to its initial acceleration, respectively, is

✓✗Two cities X and Y are connected by a regular bus service with a bus leaving in either direction every T minutes. A girl driving a scooty at 60 km/h in the direction X to Y notices that a bus goes past her every 30 minutes in the direction of her motion, and every 10 minutes in the opposite direction. Choose the correct option for the period T of the bus service and the speed (assumed constant) of the buses.

✓✗For the train of the previous question (2 m s⁻² up, 4 m s⁻² down, 30 s in all), the total distance covered is

✓✗For the ball thrown in the lift (lift moving up at 5 m/s, ball thrown at 10 m/s relative to the lift), the maximum height reached by the ball above its point of release, as seen from the ground, is (take g = 10 m s⁻²)

✓✗A car moving with a speed of 40 km/h can be stopped by applying brakes in at least 2 m. If the same car is moving with a speed of 80 km/h, what is the minimum stopping distance?

✓✗A particle moves with a retardation proportional to its velocity, \( a = -kv \). Its velocity as a function of time, starting with v₀, is