A train of 150 m length is going towards north direction at a speed of 10m/s. A parrot flies at the speed of 5 m/s towards south direction parallel to the railways track.The time taken by the parrot to cross the train is
12 s
8 s
15 s
10 s
A ball P is dropped vertically and another ball Q is thrown horizontally from the same height and at the same time. If air resistance is neglected, then,
Ball P reaches the ground first
Ball Q reaches the ground first
Both the balls reach the ground at the same time
Respective masses of the two balls will decide the time
A body dropped from top of a tower fall through 40 m during the last two seconds of its fall. The height of tower is (g = 10m/s2)
60 m
45 m
80 m
50 m
The ratios of the distance covered by a freely falling particle, starting from rest in the first, second, third ... nth seconds of its motion
Form the series corresponding to the squares of the first n natural numbers
Form an A.P.
Form a series corresponding to the difference of the squares of the successive natural numbers
Both choices (b) and (c) are correct
What will be ratio of the distance moved by a freely falling body from rest in 4th and 5th seconds of journey?
4 : 5
7 : 9
16 : 25
1 : 1
If a car at rest accelerates uniformly to a speed of 144 km/h in 20 s, it covers a distance of
2880 m
1440 m
400 m
20 m
A car covers the first – half of the distance between two places at 40 km/h and other half at 60km/h. The average speed of the car is
40 km/h
48 km/h
50 km/h
60 km/h
One train A 120 m long is moving in a direction with a speed of 20 m/s. Another train B 130 m long is moving with a speed of 30 m/s in the opposite direction. The train B crosses the train A in a time
5 s
36 s
38 s
1.25 m
2.50 m
3.75 m
5.00 m
An athlete completes one round of a circular track of radius r in 40 seconds. What will be his displacement at the end of 2 min and 20 seconds?
zero
2 R
2 π R
7 π R