Answer:
The effect of the angle between force and displacement on work.
Explanation:
When the angle between the force and displacement = zero , The work done is maximum when the direction of force is the same as the direction of displacement , such as a person pulling an object through a certain distance .
Hope that this helps you and have a great day :)
Answer: Either it's B. The seismic waves frequency also changed multiple times.
or
D. As the wave passed through less dense material, the speed of the wave increased.
Explanation: I'll let you choose because I'm stumped on which one it is. They both sound like they would fit perfectly with the question and I've tried doing research on it but nothing can prove either one right or wrong for me.
I know seismic waves can change frequency given the density of rock\ground it's going through.
"The propagation velocity of seismic waves depends on density and elasticity of the medium as well as the type of wave. Velocity tends to increase with depth through Earth's crust and mantle, but drops sharply going from the mantle to outer core."
However, B. also fits nicely.
"Temperature tends to lower the speed of seismic waves and pressure tends to increase the speed. Pressure increases with depth in Earth because the weight of the rocks above gets larger with increasing depth."
Nevertheless, I hope it helps.
Answer:
x(t) = - 6 cos 2t
Explanation:
Force of spring = - kx
k= spring constant
x= distance traveled by compressing
But force = mass × acceleration
==> Force = m × d²x/dt²
===> md²x/dt² = -kx
==> md²x/dt² + kx=0 ------------------------(1)
Now Again, by Hook's law
Force = -kx
==> 960=-k × 400
==> -k =960 /4 =240 N/m
ignoring -ve sign k= 240 N/m
Put given data in eq (1)
We get
60d²x/dt² + 240x=0
==> d²x/dt² + 4x=0
General solution for this differential eq is;
x(t) = A cos 2t + B sin 2t ------------------------(2)
Now initially
position of mass spring
at time = 0 sec
x (0) = 0 m
initial velocity v= = dx/dt= 6m/s
from (2) we have;
dx/dt= -2Asin 2t +2B cost 2t = v(t) --- (3)
put t =0 and dx/dt = v(0) = -6 we get;
-2A sin 2(0)+2Bcos(0) =-6
==> 2B = -6
B= -3
Putting B = 3 in eq (2) and ignoring first term (because it is not possible to find value of A with given initial conditions) - we get
x(t) = - 6 cos 2t
==>
Electric generators I belive hope it helps you alot
Resistance is the ratio of the potential difference between
two points and the electric current flowing between the same
two points. The unit of resistance is the "Ohm".
1 Ohm = 1 volt/ampere.