Question

Please help with 4 a-f and explain answers

e. A pole vaulter runs, plants his pole, and vaults up over the bar. 3. Identify the energy transfers that occur in each of the following processes (e.g. W->K) a. You pick up a book from the floor and place it on a table. b. You roll a bowling ball. 4. An object experiences a force while undergoing the displacement shown. Is the work done positive (+), negative ), or zero (0)? a. b. C. Sign of W d. Sign of W Sign of W- e. f. Sign of W- Sign of W Sign of w

Answer 1

Work done by a force is given by W= $Fdcos\theta$ Where $\theta$ is the angle between force and displacement

a since the angle theta is acute ,therefore work done will be positive

b angle acute ,work done will be positive

c angle again acute,work done is positive

d angle between them is obtuse ,so work done will be negative

e angle obtuse,so work done is negative

f angle between them is 180 degree ,so work done will be negative