A brick can be pushed gently on the smooth floor by applying force with our foot. But if we kick the brick, the foot is hurt. Why?

The brick shown in the figure is glued to the floor. A 3500 N force is applied to the top surface of the brick as shown. If the brick has a shear modulus of 5.4xx10^(9)N//m^(2) , how far to the right does the top face move relative to the stationary bottom face

A uniform plank is resting over a smooth horizontal floor and is pulled by applying a horizontal force at its one end. Which of the following statements are not correct?

Akash can move an iron block at rest ,placed on a metal sheet by pushing it with a force of 50 N. When a lubricant is applied on the effort is reduced to do the same activity .The force with which the block can be moved in the second case is "________" .

A wooden wedge of mass M and inclination anlgle (alpha) rest on a smooth floor. A block of mass m is kept on wedge.A force F is applied on the wedge as shown in the figure such that block remains stationary with respect to wedge So, magnitude of froce F is

The force exerted by the floor of an elevator on the foot of a person standing there is more than the weight of the person if the elevator is :

A dentist's chair with a patient in it weighs 2100 N . The output plunger of a hydraulic system begins to lift the chair when the dentist's foot applies a force of 55 N to the plunger and the piston . What is the ratio of the radius of the plunger to the radius of the piston ?

A bicycle has pedal rods of length 16 cm connected to sprocketed disc of radius 10 cm . The bicycle wheels are 70 cm in diameter and the chain runs over a gear of radius 4cm . The speed of the cycle is constant and the cyclist applies 100 N for, that is always perpendicular to the pedal rod, as shown in figure. Assume tension in the lower part of chain is negligible. The cyclist is peddling at a constant rate of two revolutions per second. Assume that the force applied by other foot is zero when one foot is exerting 100 N force. Neglect friction within cycle parts and the rolling friction. The net force of the friction on the rear wheel due to the road is:

A bicycle has pedal rods of length 16 cm connected to sprocketed disc of radius 10 cm . The bicycle wheels are 70 cm in diameter and the chain runs over a gear of radius 4cm . The speed of the cycle is constant and the cyclist applies 100 N for, that is always perpendicular to the pedal rod, as shown in figure. Assume tension in the lower part of chain is negligible. The cyclist is peddling at a constant rate of two revolutions per second. Assume that the force applied by other foot is zero when one foot is exerting 100 N force. Neglect friction within cycle parts and the rolling friction. The speed of the bicycle is

A bicycle has pedal rods of length 16 cm connected to sprocketed disc of radius 10 cm . The bicycle wheels are 70 cm in diameter and the chain runs over a gear of radius 4cm . The speed of the cycle is constant and the cyclist applies 100 N for, that is always perpendicular to the pedal rod, as shown in figure. Assume tension in the lower part of chain is negligible. The cyclist is peddling at a constant rate of two revolutions per second. Assume that the force applied by other foot is zero when one foot is exerting 100 N force. Neglect friction within cycle parts and the rolling friction. The tension in the upper portion of the chain is equal to