When we shake a mango tree, the mangoes fall. It is because when we shake the tree, the mangoes tend to be at rest due to inertia whereas the branches are in motion. That is why the mangoes fall from the branches.

Any three differences between acceleration and retardation are:

Solution:

Initial velocity of car (u) = 45 km/hr = 45 * 1000/3600 = 12.5 m/s

Time taken (t) = 3 s

Since the car stops finally, final velocity of car (v) = 0 m/s

Now,

Retardation (-a) = (u - v)/t

= (12.5 - 0)/3

= 4.17 m/s²

Hence, the magnitude of retardation of the car is 4.17 m/s².

Let the car move a distance 's' before coming into rest than from equations of motion, we have,

s = ut - 1/2 (a)t² [acceleration is negative due to retardation]

= (12.5)3 - 1/2 (4.17) (3)²

= 18.375 m

Hence, the car travelled...

Given

initial velocity ( u ) = 72 km/hr = 72 x 1000 / 3600

= 20 m/s

acceleration due to gravity (g) = 10 m/s²

also, final velocity(v) = 0 m/s

for maximum height,

v² = u² - 2gH

or, 0 = 20² - 2 x 20 H

thus, H = 400/ 40

maximum height (H) = 10 m

again , for time to return to initial position.

total displacement(s) = 0

so,

s= ut - 1/2 gt²

or, ut = gt²

thus, T = u/g

= 20/10

total time taken = 2 sec

The fan tends to continue its circular motion even after it is switched off due to the inertia of motion. The fan rotates with a decrease in speed (this is because of air friction) and stops after a few minutes.

Forces are said to be balanced when there is no net push or pull acting on the body experiencing the force. Example: balanced condition of tug of war, etc.

Forces are said to be unbalanced when there is some push or pull acting on the body experiencing the force. Example: when a team pulls another team in a tug of war, etc.

Velocity is the rate of change of displacement.

Mathematically, Velocity (V) = displacement / time

If car A travels 10 meters in 5 seconds in a straight line, it's velocity is 2 m/s.