Answer:
50
Explanation:
The mechanical advantage of a machine is given by
where
is the output force
is the input force
For the crowbar in this problem,
is the force in input applied by the worker
is the force that the machine must apply in output to overcome the resistance of the window and to open it
Substituting into the equation, we find
Answer:
Explanation:
Potential energy is the energy stored within an object, due to the object's position, arrangement or state
The center of mass is given with this formula:
Velocity is:
So, for the velocity of the center of mass we have:
In our case it is:
Answer:
K.E = 0.0075 J
Explanation:
Given data:
Mass of the ball = 1.5 kg
radius, r = 50 cm = 0.5 m
Angular speed, ω = 12 rev/min = (12/60) rev/sec = 0.2 rev/sec
Now,
the kinetic energy is given as:
K.E = 
where,
I is the moment of inertia = mr²
on substituting the values, we get
or
K.E = 0.0075 J
Greenhouse gases trap thermal energy and reflect the sun’s harmful radiation back to Earth is the answer
im not 100% sure tho
hope it helps:))
