A 800-N crate is being pushed across alevel floor at a constant speed by a force

Question

A 800-N crate is being pushed across alevel floor at a constant speed by a force of 320 N at an angle of 20.0° below the horizontal,as shown in the figure below. (a) What is the coefficient of kinetic frictionbetween the crate and the floor?


(b) If the 320 N force is instead pulling the block at an angle of20.0° above the horizontal as shown in the figure, what will bethe acceleration of the crate? Assume that the coefficient offriction is the same as that found in part (a). Any help is appreciated! Thank you! (a) What is the coefficient of kinetic frictionbetween the crate and the floor?


(b) If the 320 N force is instead pulling the block at an angle of20.0° above the horizontal as shown in the figure, what will bethe acceleration of the crate? Assume that the coefficient offriction is the same as that found in part (a). Any help is appreciated! Thank you!

Explanation / Answer

normal force=800+320*sin20=909.45 N let coefficient of kinetic friction= since the speed is constant 909.45*=320*cos20 =0.33 (ans a) part b------ now normal force=800-320*sin20=690.55 N frictional force=690.55*0.33=227.88 N unbalanced force=320*cos20-227.88=72.82 mass=800/g=800/9.8 acceleration=72.82/(800/9.8)=0.89 m/s2 (ans b)

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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