Answer:
k = 40 N/m
Explanation:
A spring's energy is given:

U is the energy in the spring, k is the spring constant and x is the spring displacement.
We are told that the spring stores 5J of energy, therefore, U = 5J. We are also told that the spring is compressed by 0.5m, so the spring x = 0.5m

k = 40 N/m
Hope this helps!
Wave C
because it is the closest or each wave is closer than the others
Answer:The rate of ejection of photoelectrons will increase
Explanation:
If the frequency of incident monochromatic light is held constant and its intensity is increased, the rate of ejection of photoelectrons from the metal surface increases with increase in intensity of the monochromatic light. More current flows due to more ejection of photoelectrons.
Answer:

Explanation:
As we know that the satellite revolves around the planet then the centripetal force for the satellite is due to gravitational attraction force of the planet
So here we will have

here we have


here we have

now we can find time period as




Now the density is given as



Answer:


Explanation:
Given



See attachment
Required
Determine PCD and CPD
First, we need to calculate CPD
Since DPA is a straight line and CPA = 100;
We have that:
--- angle on a straight theorem
Substitute 100 for CPA

Subtract 100 from both sides


Next, we calculate PCD
We have that:
--alternate angle
In triangle PCD
--- angles in a triangle
Where

So, we have:


Subtract 136 from both sides

