7. Friction, Inclines, Systems

What was the greatest discovery by Galileo during his inclined-plane experiments?

If an object of weight $w$ rests on a frictionless inclined plane, how will $w$ change if the angle of the ramp to the horizontal is increased?

While driving up a steep incline, what action should you take to maintain a constant $v$?

A $3500$ kg truck is parked on a $7.0°$ slope. What is the magnitude of the friction force acting on the truck? (Assume the truck is at rest and neglect air resistance. Use $g=9.8$ m/s$2^{\mathrm{}}$.)

A $4000\mathrm{kg}$ truck is parked on a $7.0°$ incline. What is the magnitude of the friction force acting on the truck?

If the coefficient of static friction between a car's tires and the road is $\mu s_{}$, what is the maximum angle $\theta$ of an inclined plane (hill) on which you can park the car without it sliding down?

A car is skidding to a stop while moving down a hill inclined at $20°$. Which of the following best describes the direction of the friction force acting on the car during the skid?

As a block slides down a frictionless incline, which of the following statements is true about its acceleration?

A driver needs to move a $3000lb$ load down a ramp with a $15\%$ grade. What is the component of the load's weight acting parallel to the ramp? (Assume $g=32.2\mathrm{ft}/s^2$ and neglect friction.)

When a ball is placed on an inclined plane that is raised to a vertical position, what is the magnitude of its acceleration (neglecting air resistance)?

A 4.0-kg box sits on a frictionless inclined plane that makes a 21° angle with the horizontal. It is held in place by a cord parallel to the plane. Calculate the tension in the cord.

An $8.00$-kg block of ice, released from rest at the top of a $1.50$-m-long frictionless ramp, slides downhill, reaching a speed of $2.50$ m/s at the bottom. What is the angle between the ramp and the horizontal?

A 4000 kg truck is parked on a 15° slope. How big is the friction force on the truck? The coefficient of static friction between the tires and the road is 0.90.

A rifle with a barrel length of 60 cm fires a 10 g bullet with a horizontal speed of 400 m/s. The bullet strikes a block of wood and penetrates to a depth of 12 cm. How long does it take the bullet to come to rest?