For the work-energy theorem, the work needed to stop the bus is equal to its variation of kinetic energy:
where
W is the work
Kf is the final kinetic energy of the bus
Ki is the initial kinetic energy of the bus
Since the bus comes at rest, its final kinetic energy is zero:
, so the work done by the brakes to stop the bus is
And the work done is negative, because the force applied by the brake is in the opposite direction to that of the bus motion.
Answer:
v₁ = 37.5 cm / s
Explanation:
For this exercise we can use that angular and linear velocity are related
v = w r
in the case of the spool the angular velocity for the whole system is constant,
They indicate the linear velocity v₀ = 25.0 cm / s for a radius of r₀ = 1.00 cm,
w = v₀ /r₀
for the outside of the spool r₁ = 1.5 cm
w = v₁ / r₁1
since the angular velocity is the same we set the two expressions equal
v1 = 
let's calculate
v₁ = 
v₁ = 37.5 cm / s
Power is defined as the rate at which the body is doing work:
Work is defined as displacement done by the force times that displacement:
We know that we need 62N to move the box, so when we apply this force along the path of 10m we have done:
of work.
Now we just divide that by 5s to get how much power is required:
Answer:
Resultant force, R = 10 N
Explanation:
It is given that,
Force acting along +x direction, 
Force acting along +y direction, 
Both the forces are acting on a point object located at the origin. Let the resultant force of the object is given by R. So,
Here 
R = 10 N
So, the resultant force on the object is 10 N. Hence, this is the required solution.
When two or more waves meet, they interact with each other. The interaction of waves with other waves is called wave interference. Wave interference may occur when two waves that are traveling in opposite directions meet. The two waves pass through each other, and this affects their amplitude.
