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A body of mass 10 kg is initially at rest on a horizontal surface. The coefficient of static friction between the body and the surface is 0.7, and the coefficient of kinetic friction is 0.4. A horizontal force 50 N is applied to the body. What is the friction force acting on the body?

A uniform solid sphere starts from rest and rolls down the inline of height h. What is the speed of the center of mass of the sphere at the bottom of the incline?

Consider the Atwood machine in the figure below. If the pulley is massless and m1=3m2{“version”:”1.1″,”math”:”m1=3m2″}, what is the magnitude of the acceleration of the system?

An object is displaced by r → = ( 5 m ) i ^ − ( 2 m ) j ^ {“version”:”1.1″,”math”:”\vec{r}=(5\,m)\hat{i}-(2\,m)\hat{j}”} while it is acted upon by  F → = − ( 8 N ) i ^ + ( 22 N ) j ^ . {“version”:”1.1″,”math”:”\vec{F}=-(8\, N)\hat{i}+(22\,N)\hat{j}.”}What is the work done on the object by this force?

A thin uniform rod is pivoted at one end and is rotating on a horizontal table. Its angular velocity depends on time according to the following law ω ( t ) = A t 2 + B t + C . {“version”:”1.1″,”math”:”\omega(t) = At^2+Bt+C.”} What are the units of A?

A wave is given by the equation  y ( x , t ) = ( 12  cm ) cos ⁡ ( ( 2.5  rad/m ) x − ( 6.0  rad/s ) t + π 4 ) {“version”:”1.1″,”math”:”y(x,t)=(12 \mbox{ cm}) \cos((2.5\mbox{ rad/m})x-(6.0\mbox{ rad/s})t+\frac{\pi}{4})”} What is the wavelength of this wave?

A person of mass 60 kg runs up a flight of stairs at a constant velocity in 3 seconds. The height of the flight is 1.8 m. What is the power exerted by the person?

Compute the torque on a uniform rod of length L and mass M from the figure below if the positive z direction is out of the page.

A simple pendulum named Bob has a period of small oscillations T=1 s on Earth (assume g=9.80 ms2{“version”:”1.1″,”math”:”ms2″} ).  Bob is flown to a planet X and it is found that now its’ period of small oscillations is 2 s. What is the value of specific gravity on the planet X in  m / s 2 {“version”:”1.1″,”math”:”\mbox{m}/s^2″}?

Which of the following issues was part of the Ruiz case?