Advertisements
Advertisements
प्रश्न
Multiple choice Question. Select the correct option.
A body dropped from the top of a tower reaches the ground in 4s. Height of the tower is
विकल्प
39.2 m
44.1 m
58.8 m
78.4 m
उत्तर
78.4 m
Explanation:
Initial velocity = u = 0
Time = t = 4s
As body falls downards,
so acceleration = a = + g = a = + 9.8 ms−2
(Distance) S = ut + 1/2 at
S = (0) (4) + 1/2 × 9.8 × (4)3
s = 0 + 1/2 × 9.8 × 16
S = 9.8 × 8 = 78.4 m
APPEARS IN
संबंधित प्रश्न
Fill in the following blank with suitable word :
A motorcycle has a steady……………. of 3 m/s2. This means that every………………. its…………….. increases by………….
Fill in the following blank with suitable word :
Velocity is the rate of change of……………………… It is measured in.............. .
Fill in the following blank with suitable word :
If a body moves with uniform velocity, its acceleration is ..............
Explain why, the motion of a body which is moving with constant speed in a circular path is said to be accelerated.
A bus running at a speed of 18 km/h is stopped in 2.5 seconds by applying brakes. Calculate the retardation produced.
Give one example of following motion :
Variable acceleration
The velocity-time graph of a body in motion is a straight line inclined to the time axis. The correct statement is ___________
Multiple choice Question. Select the correct option.
The speed of a car reduces from 15 m/s to 5 m/s over a displacement of 10 m. The uniform acceleration of the car is :
Draw a velocity versus time graph of a stone thrown vertically upwards and then coming downwards after attaining the maximum height.
Two stones are thrown vertically upwards simultaneously with their initial velocities u1 and u2 respectively. Prove that the heights reached by them would be in the ratio of `"u"_1^2 : "u"_2^2` (Assume upward acceleration is –g and downward acceleration to be +g)