Exam 5: Applications of Newtons Laws

A block of mass M is sliding down a rough inclined surface that makes an angle $\theta$ with respect to the horizontal.If the coefficient of static friction is $\mu$ _s and kinetic friction $\mu$ _k,then the acceleration of the block down the incline is equal to:

A block with a mass of 10 kg is at rest on a horizontal surface.The coefficient of static friction between the block and the surface is 0.30,and the coefficient of kinetic friction is 0.25.A force of 20 N acts on the block toward the left.The magnitude of the frictional force on the block is

An Atomic Force Microscope consists of a cantilever with a very fine tip on one end.The lever is driven by a piezoelectric motor allowing the tip to scan a surface on an atomic scale.As it scans the surface what is the main frictional force between the tip and the surface?

The center of mass of the system of particles shown in the diagram is at point

An L-shaped piece,represented by the shaded area on the figure,is cut from a metal plate of uniform thickness.The point that corresponds to the center of mass of the L-shaped piece is

In the equation F = bv,F is the force on an object that is moving in a viscous medium,b is a constant,and v is the speed of the falling object.The SI units of the constant b are

A 2-kg block sits on an incline where the top part of the incline has a coefficient of kinetic friction ( $\mu$ _k)of 0.70.The bottom section of the plane has $\mu$ _k = 0.95.The angle of inclination is 40 degrees.The block is released and travels 10 m along the initial part of the incline and then enters the lower section.Calculate how far the block travels along the second section before it is brought to a stop.

A car going around a curve of radius R at a speed V experiences a centripetal acceleration a_c.What is its acceleration if it goes around a curve of radius 3R at a speed of 2V?

A block is placed on a plane whose angle of inclination is 30º.The coefficients of static and kinetic friction for the block on the inclined plane are both 0.2.The block

The blocks shown in the figures have equal masses and are made of the same material.The velocity is the same in each figure.The total frictional force exerted by the surface on the blocks is

A mass M = 5.6 kg on a horizontal table is pulled by a horizontal string that passes over a frictionless pulley to a free-hanging mass m = 3.4 kg.The coefficient of friction between M and the table is 0.28.The acceleration of M is

An object traveling in a circle at constant speed

A particle is moving uniformly in a circle with radius 50 cm.The linear speed of the particle is 60 cm/s.The acceleration of the particle has a magnitude of