Answer:
2.2nC
Explanation:
Call the amount by which the spring’s unstretched length L,
the amount it stretches while hanging x1
and the amount it stretches while on the table x2.
Combining Hooke’s law with Newton’s second law, given that the stretched spring is not accelerating,
we have mg−kx1 =0, or k = mg /x1 , where k is the spring constant. On the other hand,
applying Coulomb’s law to the second part tells us ke q2/ (L+x2)2 − kx2 = 0 or q2 = kx2(L+x2)2/ke,
where ke is the Coulomb constant. Combining these,
we get q = √(mgx2(L+x2)²/x1ke =2.2nC
Answer:
b) twice the energy of each photon of the red light.
Explanation:
= Wavelength
h = Planck's constant = 
c = Speed of light = 
Energy of a photon is given by
Let 
= 700 nm
For red light
For UV light
Dividing the equations
Hence, the answer is b) twice the energy of each photon of the red light.
Objects dropped straight or thrown horizontally from the same height
change their vertical velocity at the same rate, and fall through equal
vertical distances in equal time intervals.
The statement is false.
Answer:
C) 40 N/m
Explanation:
If we ASSUME that the spring is un-stretched at the zero cm position
k = F/Δx = 10/0.25 = 40 N/m
