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Here u = 0 Using
Time (in seconds) Distance (in metres) A = 2s/t2 0 0 0 1 1 2 2 8 4 3 27 6 4 64 8 5 125 10 6 216 12 7 343 14 Hence, the force must also be increasing uniformly with time.
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Here, mass of motorcar, m = 1200 kg Let each person exert a push F on the motorcar. Total push of two persons = F + F = 2 F As this push gives a uniform velocity to the motocar along a level road, it must be a measure of the force of friction (f) between the motorcar and the road, i.e., f = 2F When three person push, total force applied F + F + F = 3F Force that produces acceleration (a = 0.2 m s-2), i.e., Ma = 3 F – f = 3 F - 2 F = F or F = ma = 1200 x 0.2 = 240 N
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The force of nail on the hammer,
Minus sign denotes the force of nail on the hammer, is acting in the direction, opposite to that of hammer.
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Here, mass, m = 1200 kg Initial velocity,
Final velocity,Time,Acceleration,(ii) Change in momentumMagnitude of change in momentum = 24000 kg(iii) Force, F = ma = 1200(-5) = - 6000 NMagnitude of force = 6000 N.
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Answer:
Let mass of truck = M Velocity of car
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(c) For an object moving along a straight path in an accelerated motion, it is not necessary that it always goes away from the earth.
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(b) According to third law of motion, action and reaction always act on different bodies in opposite directions.
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(d) The goalkeeper pulls his hands backwards after holding the ball to decrease the rate of change of momentum by increasing the time. By doing this, less force is exerted on his hands (
Force is directly proportional to the rate of change of momentum).
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(c) The inertia of an object tends to cause the object to resist any change in its state of rest or motion.
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(a) If the coin falls behind the passenger that means the train is accelerated. When the coin is tossed it has same velocity as that of train but during the time it is in air its velocity becomes less than that of train (because the train is accelerated), so it falls behind the passenger.
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(b) Given, mass m = 2 kg, velocity
As the object is moving with a constant velocity i.e.,so the acceleration of the object is zero i.e., a = 0 and according to the property of inertia if there is no external force acting on the body, then body remains as it is i.e., if the body is at rest, remains and if it is in motion remains in motion.
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(c) Rocket works on the conservation of momentum. In a rocket, the fuel burns and produces gas at high temperature. These gases are ejected out of the rocket from a nozzle at the back side of the rocket. The ejecting gas exerts a forward force on the rocket which help in accelerating. Through the mass of gases escaping per second is very small and their momentum is very large due to their tremendous velocity of escape. An equal and opposite momentum is imparted to the rocket which despite its large mass builds up a high velocity.
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(b) On the sudden application of brake, the tanker will come in the state of rest but the water remains in the state of motion, so the water will move forward.
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As the mass is a measure of inertia the ball of same shape and size having more mass than other balls will have highest inertia. Since, the steel has greatest density and greatest mass therefore it has highest inertia.
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When the train is stopped suddenly, then it comes in the state of rest but the balls remain in the state of motion. So, due to inertia of motion, the balls move in the forward direction. As the balls are of same size but of different materials that means their mass will be different. So, both the balls will move with different speeds.
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As both the bullets are identical and are fired with the same force. So, to reduce recall velocity, we use, heavy rifle so that its heavy mass compensate the large momentum. But for light rifle, recoil velocity will be large due to small mass thus light rifle will hurt more to the shoulder.
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When the cart starts moving, frictional force starts working on the wheel of cart in opposite to the motion. So, horse need to apply continuous force in forward direction to maintain constant speed.
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Momentum of a system remains conserved if no external force acts on the system. In the given example, there is gravitational force acting on the ball which is an external force, so it is not an example of conservation of momentum.
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Answer:
Given, mass,
Initial velocity,Final velocity,Time taken,From first equation of motion v = u + atAcceleration,[Negative sign shows retardation] Now, frictional force of the floor on the ball[Negative sign showns against the direction of motion]
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Let, initial mass,
Initial force,According to the question, new mass,and new force,From Newton's second law, F = maChange in accelerationHence, the new acceleration will be one-fourth of previous acceleration.
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Separation between them will increase. Initially the momentum of both of them are zero as they are at rest. In order to conserve the momentum the one who throws the ball would move backward. The second will experience a net force after catching the ball and therefore will move backward that is in the direction of the force.
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Water sprinkler works on Newton's third law of motion. When the water supplied, then force applies on the sprinkler due to which it rotates.
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If a body of mass (m), moving at velocity (u) accelerates uniformly at.(a) for time 'f, so that its velocity changes to v, then initial momentum
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We know that, Sl unit of mass, m=1kg Sl unit of acceleration, a = 1
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Momentum The quantity of motion possessed by a moving body is known as momentum of the body. Momentum of an object of mass m moving with a velocity v is the product of it. It is denoted by p p= mv Its Sl unit is
. As from Newton's lInd law, rate of change of momentum is equal to force applied. So,Hence, force applied on an produces acceleration, (i)Momentum versus velocity when mass is fixed,If m is fixed, thenMomentum versus velocity graph will be a straight line passing through the origin (if v = 0, then p = 0). (ii) Momentum versus mass graph when velocity is constant for different bodyIf velocity is constant for different masses, thenSo, the momentum versus mass graph will be a straight line passing through the origin (if m = 0, then p= 0).
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