Answer:
4000J
Explanation:
Given parameters:
Weight of the man = 800N
Height of ladder = 5m
Unknown:
Gravitational potential energy gained = ?
Solution:
The gravitational potential energy is due to the position of a body.
Gravitational potential energy = weight x height
Now insert the parameters;
Gravitational potential energy = 800 x 5 = 4000J
Answer:0.69
Explanation:
Coefficient of kinetic friction=f/R=61.8/90=0.69
Answer:
Explanation:
Given
mass of lead piece 
mass of water in calorimeter 
Initial temperature of water 
Initial temperature of lead piece 
we know heat capacity of lead and water are 
and 
respectively
Let us take 
be the final temperature of the system
Conserving energy
heat lost by lead=heat gained by water
Answer: 8.6 µm
Explanation:
At a long distance from the source, the components (the electric and magnetic fields) of the electromagnetic waves, behave like plane waves, so the equation for the y component of the electric field obeys an equation like this one:
Ey =Emax cos (kx-ωt)
So, we can write the following equality:
ω= 2.2 1014 rad/sec
The angular frequency and the linear frequency are related as follows:
f = ω/ 2π= 2.2 1014 / 2π (rad/sec) / rad = 0.35 1014 1/sec
In an electromagnetic wave propagating through vacuum, the speed of the wave is just the speed of light, c.
The wavelength, speed and frequency, are related by this equation:
λ = c/f
λ = 3.108 m/s / 0.35. 1014 1/s = 8.6 µm.
