Answer:
Spring constant of the spring will be equal to 9.255 N /m
Explanation:
We have given mass m = 0.683 kg
Time taken to complete one oscillation is given T = 1.41 sec
We have to find the spring constant of the spring
From spring mass system time period is equal to
, here m is mass and K is spring constant
So 

Squaring both side


So spring constant of the spring will be equal to 9.255 N /m
Answer:

Explanation:
Let the sphere is uniformly charge to radius "r" and due to this charged sphere the electric potential on its surface is given as

now we can say that


now electric potential is given as


now work done to bring a small charge from infinite to the surface of this sphere is given as


here we know that

now the total energy of the sphere is given as




Answer:
216 m
Explanation:
Assuming a straight line:
Δx = vt
Δx = (12 m/s) (18 s)
Δx = 216 m
I would make the ramp flatter. In doing so the ramp would have to be longer.
The amount left of a given substance can be calculated through the equation,
A = (A0) x 0.5^n/h
From the given scenario,
A/A0 = 0.75 = 0.5*(60/h)
The value of h from the equation is 144.565 minutes.