1.A shopper pushes a grocery cart with a force of 75N at a constant speed of 0.75m/s foe an hour around a store. How much work does she do on the cart?
2. A ball of mass 240g is falling through the air with a speed of 20.0 m/s at a height of 30m. With what speed will it hit the ground?
2. A ball of mass 240g is falling through the air with a speed of 20.0 m/s at a height of 30m. With what speed will it hit the ground?
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1) x = vt = (0.75)(3600) = 2700 m
W = F*x = (75)(2700) = 202500 J
2) v² = v₀² + 2ax = (20)² + 2(9.8)(30) = 988
v = √(988) = 31.432 m/s
W = F*x = (75)(2700) = 202500 J
2) v² = v₀² + 2ax = (20)² + 2(9.8)(30) = 988
v = √(988) = 31.432 m/s