Question

1. A) A block of weight mg sits on an inclined plane as shown in Figure 1A. A force of magnitude F is applied to pull the block up the incline at constant speed. The coefficient of kinetic friction between the plane and the block is $mu_k$ i) What is the work done on the block by the friction force and the applied force F as the block moves a distance L up the incline? B) Now the applied force F is changed so that instead of pulling the block up the incline, the force pulls the block down the incline at a constant speed (see Figure 1B). ii) What is the work done on the block by the friction force and by the applied force F as the block moves a distance L down the incline? Express your answers in terms of any or all of the variables $mu_k$, m, g, L, $ heta$ and F. 2. A Banked Turn With Friction. Suppose you want to negotiate a curve with a radius R and a banking angle $eta$. If the coefficient of static friction between your tires and the pavement is $mu_s$, A) what is the maximum speed that you can safely use before sliding up the banking? Draw a free-body diagram of all the forces acting on the car. B) If the coefficient of friction is zero, show that your expression can be reduced to the one obtained in class ($taneta = v^2/gR$) for the no friction case? Express your answers in terms of any or all of the variables $mu_s$, R and $eta$. 3. A box with mass m is forced against a horizontal spring of negligible mass and force constant k, compressing the spring a distance L. When released, the box slides on a horizontal tabletop with coefficient of kinetic friction $mu_k$. Use the work-energy theorem to find how far the box moves from its initial position before coming to rest. Express your answer in terms of any or all of the variables $mu_k$, m, L and k. 4. Two workhorses tow a barge along a straight canal (Figure 2). Each horse exerts a constant force of magnitude F, and the tow ropes make an angle $ heta$ with the direction of motion of the horses and the barge. Each horse is traveling at a constant speed v. A) How much work W is done by each horse in a time t? B) How much power P does each horse provide? Express your answers in terms of any or all of the quantities given in the problem (i.e. F, $ heta$, v, t).

1. A) A block of weight mg sits on an inclined plane as shown in Figure 1A. A
force of magnitude F is applied to pull the block up the incline at constant
speed. The coefficient of kinetic friction between the plane and the block is $mu_k$
i) What is the work done on the block by the friction force and the applied
force F as the block moves a distance L up the incline? B) Now the applied
force F is changed so that instead of pulling the block up the incline, the force
pulls the block down the incline at a constant speed (see Figure 1B). ii) What is
the work done on the block by the friction force and by the applied force F as
the block moves a distance L down the incline? Express your answers in
terms of any or all of the variables $mu_k$, m, g, L, $ heta$ and F.
2. A Banked Turn With Friction. Suppose you want to negotiate a curve with a radius R and a banking angle
$eta$. If the coefficient of static friction between your tires and the pavement is $mu_s$, A) what is the maximum
speed that you can safely use before sliding up the banking? Draw a free-body diagram of all the forces
acting on the car. B) If the coefficient of friction is zero, show that your expression can be reduced to the
one obtained in class ($taneta = v^2/gR$) for the no friction case? Express your answers in terms of any or all of
the variables $mu_s$, R and $eta$.
3. A box with mass m is forced against a horizontal spring of negligible mass and force constant k,
compressing the spring a distance L. When released, the box slides on a horizontal tabletop with
coefficient of kinetic friction $mu_k$. Use the work-energy theorem to find how far the box moves from its
initial position before coming to rest. Express your answer in terms of any or all of the variables $mu_k$, m, L
and k.
4. Two workhorses tow a barge along a straight canal (Figure 2). Each horse
exerts a constant force of magnitude F, and the tow ropes make an angle $ heta$
with the direction of motion of the horses and the barge. Each horse is
traveling at a constant speed v. A) How much work W is done by each horse
in a time t? B) How much power P does each horse provide? Express your
answers in terms of any or all of the quantities given in the problem (i.e. F,
$ heta$, v, t).

Added by David W.

Question

Please give Ace some feedback