Advertisements
Advertisements
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?
Advertisements
उत्तर
Here, final velocity = 20 m/s
Initial velocity = 50 m/s
Time taken = 3 s
Acceleration = `("Final Velocity" - "Initial Velocity")/"time"`
= `(20 - 50)/3` m/s−2
= −10 m/s−2
The negative sign here indicates that the velocity decreases with time, so retardation is 10 m/s−2.
APPEARS IN
संबंधित प्रश्न
State the type of motion represented by the following sketches in Figures.
Give an example of each type of motion.
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?
Figure given below shows a velocity-time graph for a car starting from rest. The graph has three parts AB, BC and CD.
(a) Is the magnitude of acceleration higher or lower than that of retardation ? Give a reason .
(b) Compare the magnitude of acceleration and retardation .
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.
Distinguish between uniformly and non-uniformly accelerated motions.
State if the following situation is possible:
A body moving with constant acceleration but with Zero velocity.
Sketch the shape of the velocity-time graph for a body moving with:
Uniform acceleration.
A car is moving with a speed of 50 km/h. One second later, its speed is 55 km/h. What is its acceleration?
m/s2 is the unit of ______.
When an object undergoes acceleration ______.
