physic hw help?

Question

work problem:
a flight attendant pulls her 70.0 N flight bag a distance of 253m along a level airport floor at constant velocity. The force she exerts is 40.0 N at the angle of 52.0 degree above the horizontal.Find the flollowing:
a)the work she does on the flight bag.
b.)the work done by the force of friction on the flight bag.
c.)the coefficient of kinetic friction between the flight bag and the floor.

Answer 1

Take the 40N @53 degrees and divide it into a horizontal and a vertical component.

a.) Since she is not lifting the bag (It stays on the floor) the vertical component does not do any work. The work is the horizontal component multiplied times the distance.

b.) The same as a.)

c.) The force on the floor is (70N-vertical component). So take the horizontal component and divide by the force on the floor.

Answer 2

Acceleration = drive / mass. Velocity = acceleration * time. Power = drive * pace #one million Assume uniform drive at every segment. In the blocks, the acceleration = five/zero.two = 20m/s² Force = 20*70 = one million,400N Out of the blocks, acceleration = (12-five)/five = 7/5m/s² Force = 7/five*70 = 98N Average vigor = ninety eight*(12+five)/two = 833W #two Conservation of power. Assume gravity = 10 m/s² (you'll use nine.eighty one when you like and you have got a calculator) Potential power at 100m relative to the bottom = 10 * one hundred * three = three,000J Potential power at 50m = one million,500J Kinetic power at 50m = one million,500J You can calculate its velocity from this: 31.6 m/s