Advertisements
Advertisements
प्रश्न
A 1000 kg vehicle moving with a speed of 20 m/s is brought to rest in a distance of 50 metres :
(i) Find the acceleration.
(ii) Calculate the unbalanced force acting on the vehicle.
Advertisements
उत्तर
(i) Final velocity, v = 0 (because the car is brought to rest)
Distance covered, s = 50 m
So, Force = mass × acceleration
But we do not know the value of a.
Making use of the third equation of motion we get,
v2 − u2 = 2as
⇒ 0 − 202 = 2 × a × 50
⇒ −400 = 100a
⇒ a = −4
The acceleration = −4 m/s2
(ii) Force = mass × acceleration
Mass = 1000 kg
Force = 1000 × (−4)
= − 4000 N
Unbalanced force acting on the vehicle is −4000 N.
APPEARS IN
संबंधित प्रश्न
An object experiences a net zero external unbalanced force. Is it possible for the object to be travelling with a non-zero velocity? If yes, state the conditions that must be placed on the magnitude and direction of the velocity. If no, provide a reason.
Give reason for the following :
When a hanging carpet is beaten with a stick, the dust particles start coming out of it.
Give one example where a force changes the direction of a moving body.
What happens to the passengers travelling in a bus when the bus takes a sharp turn ? Give reasons for your answer.

Give one example where a force stops a moving body .
When a toothpaste tube is squeezed, its shape changes. The force responsible for this is an example of :
If we release a magnet held in our hand, it falls to the ground. The force which makes the magnet fall down is an example of :
When a rubber balloon held between the hands is pressed, its shape changes. This happens because :
Which of the following effect cannot be produced by an unbalanced force acting on a body?
Why does it happen?
If a stationary bus suddenly speeds up, passengers are thrown in the backward direction.
