Advertisements
Advertisements
प्रश्न
The figure shows the displacement - time graph for four bodies A, B C and D. In each case state what information do you get about the acceleration (zero, positive or negative).

Advertisements
उत्तर
For body A: The graph is a straight line. So, the slope gives constant velocity. Hence, the acceleration for body A is zero.
For body B: The graph is a straight line. So, the slope gives constant velocity. Hence, the acceleration for body B is also zero.
For body C: The slope of the graph is decreasing with time. Hence, the acceleration is negative.
For body D: The slope of the graph is increasing with time. Hence, the acceleration is positive.
APPEARS IN
संबंधित प्रश्न
Give one example of a situation in which a body has a certain average speed but its average velocity is zero.
Fill in the following blank with suitable word :
A motorcycle has a steady……………. of 3 m/s2. This means that every………………. its…………….. increases by………….
Name the quantity which is measured by the area occupied under the velocity-time graph.
A freely falling object travels 4.9 m in 1st second, 14.7 m in 2 nd second, 24.5 m in 3rd second, and so on. This data shows that the motion of a freely falling object is a case of :
Define velocity. State its unit.
A body starts from rest and acquires a velocity 10 m s-1 in 2 s. Find the acceleration.
When is the positive acceleration?
Can you suggest a real-life example about the motion of a body from the following velocity – time graph?

A packet is dropped from a stationary helicopter, hovering at a height ‘h’ from ground level, reaches the ground in 12s. Calculate
- the value of h
- final velocity of packet on reaching the ground. (Take g = 9.8 ms−2)
An electron moving with a velocity of 5 × 104 ms−1 enters into a uniform electric field and acquires a uniform acceleration of 104 ms–2 in the direction of its initial motion.
(i) Calculate the time in which the electron would acquire a velocity double of its initial velocity.
(ii) How much distance the electron would cover at this time?
