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प्रश्न
The rate of change of velocity is ______.
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उत्तर
The rate of change of velocity is acceleration.
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संबंधित प्रश्न
Give one example of the following motion:
Uniform retardation
A body falls freely from a certain height. Show graphically the relation between the distance fallen and square of time. How will you determine g from this graph?
A space craft flying in a straight course with 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 being in action for only 6 s.
A ball is rolling from A to D on a flat and smooth surface. Its speed is 2 cm/s. On reaching B, it was pushed continuously up to C. On reaching D from C, its speed had become 4 cm/s. It took 2 seconds for it to go from B to C. What is the acceleration of the ball as it goes from B to C?
A motorbike, initially at rest, picks up a velocity of 72 kmh−1 over a distance of 40 m. Calculate
- acceleration
- time in which it picks up above velocity.
An aeroplane lands at 216 kmh−1 and stops after covering a runway of 2 m. Calculate the acceleration and the time, in which it comes to rest.
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 90 kmh−1 is slowed down to 18 kmh−1 in 2.5 s. Calculate
- acceleration
- distance covered during slow down.
What is the SI unit of acceleration?
A car traveling at 60 km/h, stops on applying brakes in 10 seconds. What is its acceleration?
The graph shows how the velocity of a scooter varies with time in 50 s.
Work out: Deceleration
A car starts from rest and it is travelling with a velocity of 20 m/s in 10 s. What is its acceleration?
Assertion: The accelerated motion of an object may be due to change in magnitude of velocity or direction or both of them.
Reason: Acceleration can be produced only by change in magnitude of the velocity. It does not depend the direction.
Exercise Problem.
A racing car has a uniform acceleration of 4 ms–2. What distance it covers in 10 s after the start?
The slope of a velocity-time graph gives ______.
When an object undergoes acceleration ______.
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?
Acceleration is a scalar.
What is the difference between uniform acceleration and non–uniform acceleration?
