A 20 N crate starting at rest slides down a rough 5.0 m long ramp, inclined at 2

Question

A 20 N crate starting at rest slides down a rough 5.0 m long ramp, inclined at 25 degrees with the horizontal. 10 J of energy is lost to friction. What will be the velocity of the crate at the bottom of the incline? a. 0.98 m/s b. 1.9 m/s c. 5.7 m/s d. 3.2 m/s e. 4.6 m/s A 0.12-kg ball is moving at 6 m/s when it is hit by a bat, causing it to reverse direction and have a speed of 14 m/s. What is the change in the magnitude of the momentum of the ball? a. 1.3 kg b. 0.390 kg c. 0.42 kg d. 2.4 kg A bobsled makes a run down an ice track starting at 150 m vertical distance up the hill. If there is no friction, what is the velocity at the bottom of the hill? a. 36 m/s b. 45 m/s c. 54 m/s d. 27 m/s

Explanation / Answer

8. mglsin(25°) - 10 = (1/2)* m *v^2

20*5*sin(25°) - 10 = (1/2)*(20/10)*v^2

v = 5.7 m/s

9. Change in momentum = Final - Initial = m*14 - m*(-6)

= 0.12* 20 = 2.4 kgm/s

10. mgh = (1/2)*m*v^2 = 54.77m/s

v = (2gh) =

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.