One of the equations of gravity is this:
Where v = final velocity which is 7m/s
u = initial velocity which is 0 for objects falling from a height
g = acceleration due to gravity and it is approximately 10m/s^2. It's a constant so pretty much remember this number. It's positive since the work being done is caused by gravity (in other words, it's falling down). It can also be negative if the work being down is against gravity (in other words, it's going up)
h = height of object
Substitute for the values and you should have something like this
Answer:
The value of radiation pressure is Pa
Explanation:
Given:
Intensity
Area of piece
From the formula of radiation pressure in terms of intensity,
Where radiation pressure, speed of light
We know value of speed of light,
Put all values in above equation,
Pa
Therefore, the value of radiation pressure is Pa
Answer:
Explanation:
First, we calculate the work done by this force after the box traveled 14 m, which is given by:
Since we have a frictionless surface, according to the the work–energy principle, the work done by all forces acting on a particle equals the change in the kinetic energy of the particle, that is:
The box is initially at rest, so . Solving for :
Answer:
21.59 m/s
Explanation:
recall that one of the equations of motions can be expressed as
v² = u² + 2as
where,
v = final velocity (we are asked to find this)
u = initial velocity = 0m/s (because it says that it starts from rest)
a = acceleration = 3.7m/s²
s = distance travelled = 63 m
simply substitute the known values above into the equation:
v² = u² + 2as
v² = 0² + 2(3.7)(63)
v² = 466.2
v = √466.2
v = 21.59 m/s