HW7 Solution

# HW7 Solution - lew(dl9564 hk7 Opyrchal(41104 This print-out...

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

lew (dl9564) – hk7 – Opyrchal – (41104) 1 This print-out should have 10 questions. Multiple-choice questions may continue on the next column or page – fnd all choices beFore answering. 001 10.0 points Given: A massless beam supporting two weights as shown in the fgure below. 964 N W L 4 L 4 L 2 L A B ±ind W such that the supporting Force at A is zero. Correct answer: 482 N. Explanation: Let : W 1 = 964 N and W 2 = W . When F A = 0, the clockwise torque will equal the counterclockwise torque at the equi- librium point O, that is W 1 L 4 = W 2 L 2 . Solution: W 2 = 1 2 W 1 = 1 2 (964 N) = 482 N . 002 (part 1 oF 2) 10.0 points The uniForm diving board shown in fgure has a mass oF 26 kg . The acceleration oF gravity is 9 . 81 m / s 2 . A B 1 . 1 m 3 . 3 m ±ind the Force on the support A when a 71 kg diver stands at the end oF the diving board. Correct answer: 2 . 34459 kN. Explanation: Let : m = 26 kg , M = 71 kg , = 4 . 4 m , x 1 = 1 . 1 m , and x d = 3 . 3 m . Consider rotational equilibrium about B : A F A F B B mg M g x 1 x 2 x 3 x d x 2 = 2 - x 1 = 1 . 1 m Applying rotational equilibrium at point B , s v τ = F A x 1 - mg x 2 - M g x d = 0 F A = p x 2 m + x d M x 1 P g = b (1 . 1 m) (26 kg) + (3 . 3 m) (71 kg) 1 . 1 m B × (9 . 81 m / s 2 ) × 1 kN 1000 N = 2 . 34459 kN .

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

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 4

HW7 Solution - lew(dl9564 hk7 Opyrchal(41104 This print-out...

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

View Full Document
Ask a homework question - tutors are online