Answer:
20N
Explanation:
The force (Hooke's Law) is proportional to the deformation. To extend the spring 4 times longer, you will need 4 times the force. In total, 20 N
Answer:
P = 0.27R from the center
Explanation:
Given,
The radius of the uniform circular plate, R = 2R
The radius of the hole, r = R
The center of the smaller circle from the center is, d = 0.8R
The center of mass of a circular disc with a hole in it given by the formula
P = dr²/R² - r²
Where P is the distance from the center of mass located in the line joining the two centers opposite to the hole.
Substituting the given values in the above equation,
P = 0.8R x R² / 4R² - R²
= 0.27R³/R²
= 0.27R
Hence the center of mass of plate is at a distant P = 0.27R from the center
Answer:
The direction of propagation is west.
Explanation:
We know that electromagnetic waves (EM-waves) are transverse in nature. EM-waves containing electric field and magnetic field both are perpendicular to the each other ( E ⊥ B ).
Transverse waves : the direction of propagation is perpendicular to the direction of amplitude which we call transverse waves. eg : light waves, water waves, gravitational waves etc.
Here, in our case the direction of electric field is pointing upward to the plan of the screen and the direction of magnetic field is pointing north
∴
×
Where
direction of electric field,
direction of magnetic field,
direction of propagation at particular instant.
Above equation follows right hand rule. put your finger toward you (out of the screen) then curl to the north side then the thumb will give you the direction of the wave propagation ( west side )
In our case west direction is the direction of wave propagation.
Relativistic mean its so fast its a fraction of the sped of light.