A train starts from rest and accelerates uniformly at a rate of 2 m s-2 for 10 s. It then maintains a constant speed for 200 s. The brakes are then applied and the train is uniformly retarded and comes to rest in 50 s. Find — (i) the maximum velocity reached, (ii) the retardation in the last 50 s, (iii) the total distance travelled, and (iv)the average velocity of the train. Open Answer »
A space craft flying in a straight course with a velocity of 75 km s-1 fires its rocket motors for 6.0 s. At the end of this time, its speed is 120 km s-1 in the same direction. Find – (i) the space craft’s average acceleration while the motors were firing (ii) the distance travelled by the space craft in the first 10 s after the rocket motors were started, the motors having been in action for only 6.0 s. Open Answer »
A car travels with a uniform velocity of 25 m s-1 for 5 s. The brakes are then applied and the car is uniformly retarded and comes to rest in further 10 s. Find — (i) the distance which the car travels before the brakes are applied, (ii) the retardation and (iii) the distance travelled by the car after applying the brakes. Open Answer »
A body moving with a constant acceleration travels the distances 3 m and 8 m respectively in 1 s and 2 s. Calculate — (i) the initial velocity, and (ii) the acceleration of body. Open Answer »
A body moves from rest with a uniform acceleration and travels 270 m in 3 s. Find the velocity of the body at 10 s after the start. Open Answer »
When brakes are applied to a bus, the retardation produced is 25 cm s-2 and the bus takes 20 s to stop. Calculate – (i) the initial velocity of bus, and (ii) the distance travelled by bus during this time. Open Answer »
A car travels a distance 100 m with a constant acceleration and average velocity of 20 m s-1. The final velocity acquired by the car is 25 m s-1. Find: (i) the initial velocity and (ii) acceleration of car. Open Answer »
A train is moving with a velocity of 90 km h-1. It is brought to stop by applying the brakes which produce a retardation of 0.5 m s-2. Find (i) the velocity after 10 s, and (ii) the time taken by the train to come to rest. Open Answer »
A train travels at a speed of 60 km h-1 from station A to station B and then comes back at a speed of 80 km h-1 from station B to station A. Find — (i) the average speed, and (ii) the average velocity of the train. Open Answer »
A train moving with a velocity of 20 m s-1 is brought to rest by applying brakes in 5 s. Calculate the retardation. Open Answer »