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!
Answer:
0.0021576N
Explanation:
F=(k)(q1q2/r^2)
F=(8.99×10^9)(3×10^-6)(2×10^-6)/(5^2)
F=0.0021576N
Answer:
1185 N
Explanation:
From Newton’s second law of motion,
F=ma where m= mass of motorcycle, a is acceleration of the motorcycle and F=Force
Net force acting on motorcycle
is given by
Where F is force acting on motorcycle and f is frictional force
Substituting F-f for
hence ma= F- f Substituting a with 3, m with 245Kg and f with 450N as provided
245*3= F- 450
F=245*3 +450= 1185 N
I would choose B. exosphere. Astronomers study outer space, planets and ect.