A shopper in a supermarket pushes a cart with a force of 34.0 N directed at an a

Question

A shopper in a supermarket pushes a cart with a force of 34.0 N directed at an angle of 25.0 degree below the horizontal. The force is just sufficient to balance various friction force so the cart moves at constant speed. (a) Find the work done by the shopper on the cart as she moves down a 45.3-m-long aisle. J (b) The shopper goes down the next aisle, pushing horizontally and maintaining the same speed as before. If the work done by frictional forces doesn't change, would the shopper's apples force be larger, smaller, or the same? larger smaller the same (c) What about the work done on the cart by the shopper? The work is larger in part (a). The work is larger in part (b). The work is the same in both parts.

Explanation / Answer

1.Fx=Fcos(theta)
Fx=(34)(cos25)
Fx=30.81N

Then to find energy we do W=Fd

W=30.81(45.3)
W=1395.693J

2.b) The work done on the cart is zero because there is no change in its mechanical energy.

c) If the applied force were horizontal, all of it would counter friction, so only 30.81 N would be needed. The reasoning of part b applies again.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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