Advertisements
Advertisements
प्रश्न
Give the magnitude and direction of the net force acting on a cork of mass 10 g floating on water.
उत्तर
Since the cork is floating on water, its weight is balanced by the upthrust, which is equal to the weight of the displaced water. Hence, the net force on the cork is zero.
APPEARS IN
संबंधित प्रश्न
Give the magnitude and direction of the net force acting on a kite skillfully held stationary in the sky.
Give the magnitude and direction of the net force acting on a car moving with a constant velocity of 30 km/h on a rough road.
Give the magnitude and direction of the net force acting on a high-speed electron in space far from all material objects, and free of electric and magnetic fields.
A pebble of mass 0.05 kg is thrown vertically upwards. Give the direction and magnitude of the net force on the pebble,
- during its upward motion,
- during its downward motion,
- at the highest point where it is momentarily at rest. Do your answers change if the pebble was thrown at an angle of 45° with the horizontal direction? Ignore air resistance.
Give the magnitude and direction of the net force acting on a stone of mass 0.1 kg, just after it is dropped from the window of a stationary train. Neglect air resistance.
Give the magnitude and direction of the net force acting on a stone of mass 0.1 kg, just after it is dropped from the window of a train accelerating with 1 m s–2. Neglect air resistance.
Give the magnitude and direction of the net force acting on a stone of mass 0.1 kg, lying on the floor of a train which is accelerating with 1 m s–2, the stone being at rest relative to the train. Neglect air resistance.
Explain why passengers are thrown forward from their seats when a speeding bus stops suddenly.
The velocity of a body of mass 2 kg as a function of t is given by `v(t) = 2t hati + t^2hatj`. Find the momentum and the force acting on it, at time t = 2s.
A cricket bowler releases the ball in two different ways
- giving it only horizontal velocity, and
- giving it horizontal velocity and a small downward velocity. The speed vs at the time of release is the same. Both are released at a height H from the ground. Which one will have greater speed when the ball hits the ground? Neglect air resistance.
