Advertisements
Advertisements
प्रश्न
Give a scientific reason.
When an object falls freely to the ground, its acceleration is uniform.
उत्तर
When an object falls freely to the ground, it is under the effect of a constant force known as the force of gravity. No other forces act on it. Hence, from Newton's second law of motion, we can say that this constant force of gravity accelerates the freely falling object uniformly. This uniform acceleration is known as acceleration due to gravity which acts towards the centre and is denoted by g.
APPEARS IN
संबंधित प्रश्न
A body is moving vertically upwards. Its velocity changes at a constant rate from 50 m s-1 to 20 m s-1 in 3 s. What is its acceleration?
The velocity-time graph for a uniformly retarded body is a straight line inclined to the time axis with an obtuse angle. How is retardation calculated from the velocity-time graph?
Draw a graph for acceleration against time for a uniformly accelerated motion. How can it be used to find the change in speed in a certain interval of time?
Draw velocity – time graph for the following situation:
When a body is moving with variable velocity, but uniform retardation.
From the diagram given below, calculate deceleration.
Diagram is given below shows velocity – time graph of car P and Q, starting from the same place and in the same direction. Calculate the Acceleration of car Q between 2 s – 5 s.
A cyclist driving at 5 ms−1, picks a velocity of 10 ms−1, over a distance of 50 m. Calculate
- acceleration
- time in which the cyclist picks up above velocity.
A truck running at 90 kmh−1, is brought to rest over a distance of 25 m. Calculate the retardation and time for which brakes are applied.
A racing car, initially at rest, picks up a velocity of 180 kmh−1 in 4.5 s. Calculate
- acceleration
- distance covered by the car.
A motor bike running at 5 ms−1, picks up a velocity of 30 ms−1 in 5s. Calculate
- acceleration
- distance covered during acceleration.
Can you use the relation [B1]?
What happens to the stepwise increasing speed-time graph when the size of each step is made very small?
Convert the following acceleration:
7200 km/h2 into m/s2
Negative acceleration is called ______.
The Unit of acceleration is ______.
A bus accelerating with 4ms-2 changes its speed from 60ms_1 to a certain value in 5s. The final speed is ______.
A boy throws a ball up and catches it when the ball falls back. In which part of the motion the ball is accelerating?
If a body starts from rest, what can be said about the acceleration of the body?
The value of acceleration for a body at rest is ______.
An object can be moving with uniform speed but with variable acceleration.
