Aworker stands on a support and with the of a block will lift the load evenly, the weight of which is 480 h (fig. 216). calculate the pressure produced by the support worker, if his weight is 720 n, and the foot area is 320 cm² (friction and block weight can be neglected.)

Explanation:

Draw free body diagrams for the worker and the load.

The worker has three forces on him: normal force pushing up, weight pulling down, and tension pulling down.

The load has three forces on it: weight pulling down and two tension forces pulling up.

Sum of the forces on the load:

∑F = ma

2T - 480 N = 0

T = 240 N

Sum of the forces on the worker:

∑F = ma

N - 720 N - 240 N = 0

N = 960 N

So the pressure produced by the worker is:

P = F / A

P = 960 N / 320 cm²

P = 3 N/cm²

P = 30,000 Pa

6.08

Explanation:

Given that,

Current, I = 0.8 A

Time, t = 76 h

We need to find the Ah rating of a battery. It can be calculated by taking the product of current and time. So,

Ah = (0.8)(76)

= 6.08 Ah

So, the Ah rating of the battery is 6.08.