Math 173 Spring 2009 6.6 Handout
1. A 200 lb person is to be lifted onto a platform 10 feet above the ground using a 10 foot
rope. If the rope weighs a total of 5 lbs, how much work is done?
2. A rectangular tank has a base of 2 feet by 4 feet and a vertical height of 3 feet. If the tank
is full of water (density = 62.4 pounds per cubic foot), find the work required to pump the
water 2 feet above the tank.
3. A spherical tank with interior radius of 4 ft is buried 1 ft below ground level. If the tank is
half full of water, how much work is done in pumping the water to ground level?
4. You need to lift a 5lb bucket containing 2 gal (16 lb) of water from the ground onto a
platform 20 feet high. You have 10 ft of chain weighing a total of 5 lbs and 10 ft of rope
weighing a total of 2 lbs. If the rope is tied to the bucket (and also to the chain), how
much work is done in lifting the water onto the platform?
5. A 200 lb calf is to be lifted onto the back of a truck 5 feet above the ground. It is lifted by
a farmer standing on a platform 15 feet above the ground using a rope weighing 2 lb/ft.
How much work is required?