Answer:
Explanation:
Given
Force 
one at an angle of 
East of North and another at West of North
Net Force is in North Direction
Forces in horizontal direction will cancel out each other
thus Work done will be by north direction forces
here 
Answer:
x ≤ 3.6913 m
Explanation:
Given
Mrod = 44.0 kg
L = 4.90 m
Tmax = 1450 N
Mman = 69 kg
A: left end of the rod
B: right end of the rod
x = distance from the left end to the man
If we take torques around the left end as follows
∑τ = 0 ⇒ - Wrod*(L/2) - Wman*x + T*Sin 30º*L = 0
⇒ - (Mrod*g)*(L/2) - (Mman*g)*x + Tmax*Sin 30º*L = 0
⇒ - (44*9.8)*(4.9/2) - (69*9.8)*x + (1450)*(0.5)*(4.9) = 0
⇒ x ≤ 3.6913 m
The energy of a wave will remain constant if which of the following changes are made to it is given below
Explanation:
1.In electromagnetic waves, energy is transferred through vibrations of electric and magnetic fields. In sound waves, energy is transferred through vibration of air particles or particles of a solid through which the sound travels. In water waves, energy is transferred through the vibration of the water particles.
2.First of all for light which is a electromagnetic wave c=frequency*wavelength. As the wavelength increases the frequency decreases. This can be physically understood as the increase in red shift of the light. Also energy =h*frequency,hence increasing wavelength decreases the energy carried by the photon.
3.Wave frequency is related to wave energy. the more energy in a wave, the higher its frequency. The lower the frequency is, the less energy in the wave.
Answer:
1. Emma standing on top of mountain
Since she is at the rest position and at some height from the ground so here energy is due to gravitational potential energy
So we have
gravitational potential energy
2. Emma jumping down from mountain top
Due to free fall Emma will start moving with some speed in downwards direction so here we have
motion energy
3. tension in rope at Emma’s lowest position
Due to stretch in the rope here position come to the lowest end and speed comes to zero so whole energy is converted into elastic potential energy
elastic potential energy
4. Emma bouncing back
Due to bouncing back she will again have its kinetic energy with some speed upwards
motion energy
The total momentum of the system is preserved through the collision.
Note that momentum is
P = m*v
where m = mass
v = velocity.
Initial momentum:
P1 = (30000 kg)*(2 m/s) = 60000 (kg-m)/s for the moving car
P2 = 0 for the starionary car.
Final momentum:
P3 = (30000 + 30000)*v = 60000v (kg-m)/s
Because momentum is preserved,
P3 = P1 + P2
60000v = 60000
v = 1 m/s
The final velocity is 1 m/s.
Answer: 1.0 m/s
