Answer: F = 131.7N
Explanation:
You are given the following parameters.
Mass M = 30 kg
Coefficient of static friction μ = 0.5
Ø = 30 degrees
When the person is trying to drag the box with force F, the static frictional force Fs will be acting in the opposite direction.
From the figure attached, resolve all forces into horizontal component and vertical component.
Horizontal component:
Fs - F cosØ = 0
Fs = F cosØ
F cosØ = μN ...... (1)
Vertical component:
N + F SinØ - mg = 0
N = Mg - F SinØ ..... (2)
Substitutes m, g and Ø into the equation 2
N = (30 × 9.8) - F × sin30
N = 294 - 0.5F
Substitute N and coefficient of friction into the equation (1)
F cos30 = 0.5 (294 - 0.5F)
Open the bracket
0.8660F = 147 - 0.25F
Collect the like terms
1.116025F = 147
F = 147/1.116025
F = 131.7 N
Therefore, the minimum force the person needs to have to move the box along the floor is 131.7 N
Technically, we can't answer the question with the given information.
Even though the cart's speed is constant, it may be turning an corner,
or driving along a curved path. If it's not driving in a straight, then there
must be some force acting on it.
If the cart IS driving in a straight line, AND its speed is constant, then
there can't be any net force acting on it. In that case, the correct choice
is ' B '. (I'm sure this is right IF the cart is driving in a straight line.)
If it's a small object near another gigantic object, then we usually call that the small object's "weight".
Answer: The surface of the pad pushes the rocket up while gravity tries to pull it down. As the engines are ignited, the thrust from the rocket unbalances the forces, and the rocket travels upward. Later, when the rocket runs out of fuel, it slows down, stops at the highest point of its flight, then falls back to Earth.
<span>work = 500*3 = 1500 J
1500J in 5 sec = 300 watts
Hope that helps:)</span>
