132k views
5 votes
If a student tried to lift a 350 N box upwards with a lever that is 75 cm long, how much force would they need to provide given a fulcrum 20 cm away from the box. 1312.5 N. 93.3 N. 65.6N. 2333N.

User Carleen
by
8.4k points

2 Answers

6 votes

Answer:

93.3 N

Step-by-step explanation:

Applying the equation of moment

M = r * F

r = distance from the applied force to the object = 75 cm

F = force applied = X

Moment of force = load * distance from load = 350 * 20

back to equation

350 * 20 = X * 75

7000 = 75 X

X ( force applied/needed) = 7000 / 75 = 93.3 N

User Dzhuang
by
8.4k points
2 votes

We will take moment about the fulcrum point

Taking, box 350 N at a distance of 20 cm

we can write the moment equation as below:

350 N x 20 cm - X x 75 cm = 0

X = 350 N x 20 cm /75 cm

= 93.33 N



User Shlomit
by
7.9k points