Answer:
F = 75[J]
Explanation:
We know that work is defined as the product of force by distance.
In this way we have two forces, the weight of the block down, and the force that bring about the block to rise.
where:
W = work = 50 [J]
d = distance = 2 [m]
Fweight = 50 [N]
Fupward [N]
Now replacing:
![50=-(50*2)+(F_{upward}*2)\\50+100=F_{upward}*2\\F_{upward}=150/2\\F_{upward}=75[J]](https://tex.z-dn.net/?f=50%3D-%2850%2A2%29%2B%28F_%7Bupward%7D%2A2%29%5C%5C50%2B100%3DF_%7Bupward%7D%2A2%5C%5CF_%7Bupward%7D%3D150%2F2%5C%5CF_%7Bupward%7D%3D75%5BJ%5D)
Answer:
Δy = v₀t + (1/2)gt²
where g = 9.81 m/s if the body is moving downwards and g = -9.81 m/s if the body is moving upwards
Explanation:
The general kinematic equation for horizontal displacement is gives as:
Δx = v₀t + (1/2)at²
Where
Δx = change in the x direction
v₀ = initial velocity
t = time
a = acceleration
If the body is vertically instead of horizontally, Δx is changed to Δy
Δy = v₀t + (1/2)at²
For a vertical moving body, the acceleration it experiences is the gravitational accerelation of the earth 'g'
So the equation becomes:
Δy = v₀t + (1/2)gt²
where g = 9.81 m/s if the body is moving downwards and g = -9.81 m/s if the body is moving upwards
