John can run with the velocity of 5 m/s
Explanation:
- Kinetic energy is defined as the energy is being used to do an activity, basically energy associated with the motion of objects in the universe.
- The formula used to find the kinetic energy of an object is k =
where as k represented as kinetic energy, m is the mass of the object and v is the velocity of the given object.
- Here, to find the answer we have to re-write the equation as
![v = \sqrt[2]{\frac{2 k}{m} }](https://tex.z-dn.net/?f=v%20%3D%20%5Csqrt%5B2%5D%7B%5Cfrac%7B2%20k%7D%7Bm%7D%20%7D)
- Given, the mass of the object, here it is John = 80 kg, energy needs to be converted to kinetic energy, k = 1000 J.
- Hence, substitute all the values, then you would velocity as 5 m/s
Answer: The shortest time the truck could take is 4.34 secs
Explanation: Please see the attachments below
(a) 
The change in energy of the transferred charge is given by:
where
q is the charge transferred
is the potential difference between the ground and the clouds
Here we have
So the change in energy is
(b) 7921 m/s
If the energy released is used to accelerate the car from rest, than its final kinetic energy would be
where
m = 950 kg is the mass of the car
v is the final speed of the car
Here the energy given to the car is
Therefore by re-arranging the equation, we find the final speed of the car:
Time period of fan (t) = 1 / 2 = 0.5 seconds
Angular velocity (ω)= 2π/t
ω = 4π
v = ωr
v = 4π x 0.61
v = 7.66 m/s
