Newton’s law of motion
1) Distinguish between static friction, limiting friction and kinetic friction. How do they vary with the applied force? Explain by a diagram.
2) State the laws of conservation of linear momentum. Prove it by using the second law of motion. Give two situations where linear momentum remains conserved.
3) Define impulse. Discuss graphical method for the measurement of impulse when a variable force acts on a body.
4) State and explain Newton’s second law of motion.
5) Derive a relation for the optimum velocity of negotiating a curve by a vehicle in a banked curve.
6) Define centripetal force. Find an expression for it.
7) Define centripetal acceleration. Derived centripetal acceleration.
8) Define force of friction. How does reduce the frictional force.
9) Derived the acceleration for inclined plane in free body diagram.
Answers
Explanation:
ans 1. The static friction is a friction that acts on a body at rest. ... Kinetic friction is the frictional force that action a body which is in motion. On increasing the applied force, static friction increase, until it reaches limiting friction which is fixed, and kinetic friction also remains constant.
ans 2. Conservation of Linear Momentum Formula
The principle of conservation of momentum states that if two objects collide, then the total momentum before and after the collision will be the same if there is no external force acting on the colliding objects.
ans 3. Impulse:- It is defined as the product of the force and the time for which the force acts. In S.I. system, the unit of impulse is newton-second (Ns). ... In this case, the force-time graph is a straight line AB, parallel to the time-axis (Figure).
ans 4. Newton's second law of motion states that the acceleration of a system is directly proportional to and in the same direction as the net external force acting on the system, and inversely proportional to its mass. In equation form, Newton's second law of motion is a=Fnetm a = F net m .
ans 5. Suppose an object of mass 'm', Radius Of the curved road 'r'.... In this case of circular motion, Centripetal
force is necessary
-->> Centripetal Force = Force of Friction
(Which means Centripetal force is provided by the force of friction between road and tyres)
Lets be the coefficient of friction(l cant find the symbol here)
'v' the velocity(optimum, What u need)
So, by definition
mv^2/r = 1mg
v^2 = ¶rg
a
ans 6. a force which acts on a body moving in a circular path and is directed towards the center of the circular path. The expression for it is. F=mv2/r=mrw2=mwv. Directed towards the center.
ans 7. The centripetal acceleration is defined as the rate of change of the tangential velocity. The centripetal force is the force that makes the body rotate in the circular path whose force acts inwards towards the centre of the rotation.
ans 8. Friction is the force resisting the relative motion solid surface, liquid layer, and material element sliding against each other.
There are several types of friction.... Method to reduce friction are:
1. Make the surface smooth. u Rough surface produce more friction and smooth surface produce less friction.
2. Reducing the force acting on on the
surface.
3. Reduce the contact between the surface.
4. Make the surface more stermline.
ans 9. As the angle is increased, the acceleration of the object is increased. ... As the angle increases, the component of force parallel to the incline increases and the component of force perpendicular to the incline decreases. It is the parallel component of the weight vector that causes the acceleration.
