If the tension in the cable supporting an elevator is equal to the weight of the elevator, the elevator may _______.

The dimension of Impulse is _______.

A force of 200 N is required to push a car of mass 500 kg slowly at constant speed on a level road. If a force of 500 N is applied, the acceleration of the car (in m S^-2) will be_______.

A block of mass m is placed on a smooth inclined plane of inclination \(\theta\) with the horizontal. The force exerted by the plane on the block has a magnitude _______.

An insect is crawling up on the concave surface of a fixed hemispherical bowl of radius R. If the coefficient of friction is \({1\over3}\) then the height up to which the insect can crawl is nearly,_______.

Water is poured from a height of 10m into an empty barrel at the rate of 1 litre per second. If the weight of the barrel is 10 kg, the weight indicated at time t = 60 s will be _______.

The physical quantity which is equal to the change in momentum of a body is known as _______.

If the speed of stone is increased beyond the maximum permissible value and the string breaks suddenly, which of the following correctly describes the trajectory of the stone after the string breaks the stone flies off tangentially from the instant the string breaks

What is the apparent weight felt by a person in an elevator, when it is accelerating: (i) upward (ii) downward?

Which law of motion is involved in rocket propulsion?

Rubber tyres are preferred over steel tyres. Why?

A helicopter of mass 1000 kg reises with a vertical acceleration of 15m /s². The crew and the passengers weigh 300 kg. Give the magnitude and direction of the
(i) force on floor by the crew and passengers.
(ii) action of the rotor of the helicopter on the surrounding air
(iii) force on the helicopter due to the surrounding air, take g = 10 m/s².

Ten one-rupee coins are put on top of each other on a table. Each coin has mass m. Give the magnitude and direction of  the force on the 7th coin by the 8 coin, (counted from the bottom).

Show that the total linear momentum of an isolated system of interacting particles is conserved.

A 20 kg box is gently placed on a rough inclined plane of inclination 30° with horizontal. The coefficient of sliding friction between the box and the plane is 0.4. Find the acceleration of the box down the incline.

In a circus, the diameter of globe of death is 30 m. From what minimum height must a cyclist start in order to roll down the inclined and go round the globe successfully?

An artificial satellite of mass 2500 kg is orbiting around the earth with a speed of 4 kms^-1 at a distance of 10^-4 from the earth. Calculate the centripetal force action on it.

A bend in a level road has a radius of 100 m. Find the maximum speed which a car turning this bend may have without skidding if the coefficient of friction between the tyres and road is 0.8.