Magnets can exert a push or pull on objects without making contact with them.

A small of mass m starts from rest at the position shown and slides along the frictionless loop the loop track of radius R. What is the smallest value of y such that the object will slide without losing contact with the track?

A student pulls a wooden box along a rough horizontal floor( without the block loosing contact with the floor) at constant speed by means of a force P as shown to the right. (W is weights of block, N is normal reaction on the block, f is force of friction on the block). which of the following must be true?

The conduction of heat can take place within an object or between any two objects in contact with each other. It stops when the objects obtain the same temperature

Assertion A car moves along a road with uniform speed. The path of car lies in vertical plane and shown in fighre. The radius of curvature (R) of the path is same everywhere. If the car does not loose contact with road at the highest point, it can travel the shown path without loosing contact with road anywhere else. Reason For car to loose contact with road, the normal reaction between car and road should be zero.

Assertion: If an object is submerged in fluid at rest, the fluid exerts a force on its surface. Reason: The force exerted by the fluid at rest has to be parallel to the surface in contact with it.

Assertion : Insert electrolytes like KCl, KNO_(3) are used in salt bridge. Reason : Salt bridge provides an electric contact between the two solutions without allowing them to mix with each other.

The radius of the bump on a road is r. What force does the road exert on a car of mass m when the car passes the highest point on the bump ? Calculate the maximum speed with which the car can pass the highest point before losing contact wtih the road ?

A Rubber Ball Rebound A rubber ball of mass 2.0kg falls to the floor. The ball hits with a speed of 8m/s and rebounds with approximately the same speed. High speed photographs show that the ball is in contact with the floor for 10^-3s. What can we say about the force exerted on the ball by the floor?

Which polymer can be used for making contact lenses for eyes

The cation/anion radius ratio for a triangular arrangement of anions in which the cation is in contact with the anions (but does not push them apart) as shown in the figure is