Recitation Worksheet I Solutions

# Recitation Worksheet I Solutions - Worksheet I Work and...

This preview shows pages 1–2. Sign up to view the full content.

Worksheet I: Work and energy. 1. A 10.0-kg crate is pulled 15.0 m up along a frictionless incline as shown in the figure below. The crate starts at rest and has a final speed of 6.00 m/s. a. Draw the free-body diagram for the crate. b. Find the work done by the weight. () ( ) 2 10.0 kg 9.8 m/s 15 m sin 25 620 J Wm g h =− °=− (negative because weight points down and vertical displacement is up) c. Find the work done by the normal force exerted by the incline on the crate. 0 (the normal force is perpendicular to the displacement) d. Find the work done by the tension on the rope. You can do this both using the work- kinetic energy theorem or using Newton’s laws and the definition of work. You should be able to do both. WKE: net 2 1 620 J 0 (10.0 kg) 6.0 m/s 0 2 800 J gNT T T WW W W K W W =++= −+ + = = Newton’s laws: ( ) ( ) ( ) ( ) 2 22 2 0 2 6.0 m/s sin with 1.2 m/s 1 5 m sin 10.0 kg 1.2 9.8sin 25 m/s 53.4 N 53.4 N 15 m 800 J T vv Tm g m a a x ag WT x θ −= = = = =+ = + ° = =∆= = motor 25 ° 15 m N mg T

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
(Worksheet I) 2. A box of mass M = 1.5 kg is pushed against a horizontal spring of constant k = 1000 N/m. The spring is compressed a distance
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 2

Recitation Worksheet I Solutions - Worksheet I Work and...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online