1. Your light truck weighs 3,500 kg. You drive up a gentle slope that is 0.5 km long. at the top of the slope you are 200 m higher in elevation than when you started. Assuming no friction, what force has your engine exerted to drive up this slope?
A. 7000N
B. 12,000N
C. 14,000N
D. 20,000N
2. In Physics the "desire of an object to keep doing what it is doing" is termed _______.
a. permanence
b. obstinacy
c. resiliency
d. inertia
3. John loads a collapsed inflatable boat into a two wheel "grocery type" handcart and wheels it down to the lake. While the cart is being wheeled it is tipped at about a 45-degree angle (in other words, about halfway between horizontal and vertical). John finds this tiring because he has to pull fairly hard to move the cart. After hearing a friends suggestion, he tries an experiement. He uses an eight-foot long board to lengthen the underside of the cart. (the side of the cart that faces downward while the cart is tipped and being pulled along). The end of the board serves as a new extended handle for his cart. Now when he goes to pull his longer cart, he is pulling the cart at a 20-degree angle (much closer to the ground than before. What will happen?
A. The cart will be even harder to pull now because it is lower to the ground.
B. The cart will be even harder to pull now because of the extra weight of the board
C. The cart will be easier to pull, in spite of the weight of the board, because now the angle of pull is much closer to the angle of movement
D. There is no real change because it takes the same amount of work to pull a given amount of weight no matter how you pull it.
You Set up a pulley to help you lift something. You anchor the rope at one end and arrange a moveable pulley to achieve a mechanical advantage of 2. By the time you have lifted the object 5m off the ground, how much rope have you pulled through the pulley?
a. 2m
b. 5m
c. 7m
d. 10m
160J of work was needed in order to move an object 8m across a floor. What was the force (in N) that was needed to do the job?
a. 20N
b. 30N
c. 40N
d. 60N
When comparing the force that is required to climb a mountain by walking up a trail that slopes gently upward to the top versus getting there by scaling a sheer vertical ciff face, which of the following is a TRUE statement?
a. You use more force for a given distance of movement on the walk than the climb
b. Walking up the trail forces you to cover a greater distance, but the amount of force needed to cover a given distance will be less.
c. Scaling the vertical cliff, while dangerous, uses less force than going the gentler way around.
d. The distance covered is the same either way, but scaling the cliff is harder because you are working against gravity.
THANKS IN ADVANCE!
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