Talking about a quantity of inertia is exactly the same as talking about a quantity of mass. So, if the boxes are anywhere near the same size, then the box of books has <u><em>more</em></u> inertia than the box of cotton balls, because books have more mass than an identical volume of cotton.
Answer:
If the ray of light is deflected by 45 degrees by the first mirror its total deflection by mirror (I) is 90 deg. (incident = 45 and exit ray equals 45 deg)
The second mirror will cause a net deflection of 90 degrees and the total deflection will be 180 deg or in opposite direction to the incident ray.
Answer:
The tension in string is found to be 188.06 N
Explanation:
For the vibrating string the fundamental frequency is given as:
f1 = v/2L
where,
f1 = fundamental frequency = 335 Hz
v = speed of wave
L = length of string = 28.5 cm = 0.285 m
Therefore,
v = f1 2L
v = (335 Hz)(2)(0.285)
v = 190.95 m/s
Now, for the tension:
v = √T/μ
v² = T/μ
T = v² μ
where,
T = Tension
v = speed = 190.95 m/s
μ = linear mass density of string = mass/L = 0.00147 kg/0.285 m = 5.15 x 10^-3 kg/m
Therefore,
T = (190.95 m/s)²(5.15 x 10^-3 kg/m)
<u>T = 188.06 N</u>
When we shake a mango tree, the mangoes fall down. It is because when we shake the tree, the mango tend to be rest due to inertia where as the branches are in motion. That is why the mangoes tend to be at rest due to inertia where as the branches are in the motion.
Answer:
a. speed, v = 0.97 c
b. time, t' = 20.56 years
Given:
t' = 5 years
distance of the planet from the earth, d = 10 light years = 10 c
Solution:
(a) Distance travelled in a round trip, d' = 2d = 20 c = L'
Now, using Length contraction formula of relativity theory:
(1)
time taken = 5 years
We know that :
time = 
5 =
(2)
Dividing eqn (1) by v on both the sides and substituting eqn (2) in eqn (1):
Squaring both the sides and Solving above eqution, we get:
v = 0.97 c
(b) Time observed from Earth:
Using time dilation:


Solving the above eqn:
t'' = 20.56 years