Answer:
Its length is measured to be 0.5 m
Explanation:
From theory of relativity (mass variation), we know that:
m = mo/√(1-v²/c²)
Where, m = relative mass
and, mo = rest mass
The momentum of stick while moving, will be:
P = mv
but, it is given in the form of rest mass as:
P = 2(mo)v
thus, by comparison;
2(mo)v = mv
using value of m from theory of relativity;
2(mo)v = (mo)v/√(1-v²/c²)
√(1-v²/c²) = 1/2 ______ eqn(1)
Now, for relativistic length (L), we have the formula from same theory of relativity;
L = (Lo)√(1-v²/c²)
The rest length (Lo) of meter stick is 1 m, and the remaining term on right side √(1-v²/c²), known as Lorentz Factor, can be given by eqn (1), as equal to 1/2.
Thus,
L = (1 m)(1/2)
<u>L = 0.5 m</u>
This question is based on the fundamental assumption of vector direction.
A vector is a physical quantity which has magnitude as well direction for its complete specification.
The magnitude of a physical quantity is simply a numerical number .Hence it can not be negative.
A negative vector is a vector which comes into existence when it is opposite to our assumed direction with respect to any other vector. For instance, the vector is taken positive if it is along + X axis and negative if it is along - X axis.
As per the first option it is given that a vector is negative if its magnitude is greater than 1. It is not correct as magnitude play no role in it.
The second option tells that the magnitude of the vector is less than 1. Magnitude can not be negative. So this is also wrong.
Third one tells that a vector is negative if its displacement is along north. It does not give any detail information about the negativity of a vector.
In a general sense we assume that vertically downward motion is negative and vertically upward is positive. In case of a falling object the motion is vertically downward. So the velocity of that object is negative .
So last option is partially correct as the vector can be negative depending on our choice of co-ordinate system.
Answer:
5
Explanation:
Number of habitable planets = 1000
Fraction of planet with life = 1/10
Fraction of planet with life and civilization (before) = 1/4
Fraction of planet with life and civilization (now) =1/5
Therefore multiplying we have:
1000×1/10×1/4×1/5 = 5
Answer:
Explanation:
Given that, .
R = 12 ohms
C = 500μf.
Time t =? When the charge reaches 99.99% of maximum
The charge on a RC circuit is given as
A discharging circuit
Q = Qo•exp(-t/RC)
Where RC is the time constant
τ = RC = 12 × 500 ×10^-6
τ = 0.006 sec
The maximum charge is Qo,
Therefore Q = 99.99% of Qo
Then, Q = 99.99/100 × Qo
Q = 0.9999Qo
So, substituting this into the equation above
Q = Qo•exp(-t/RC)
0.9999Qo = Qo•exp(-t / 0.006)
Divide both side by Qo
0.9999 = exp(-t / 0.006)
Take In of both sodes
In(0.9999) = In(exp(-t / 0.006))
-1 × 10^-4 = -t / 0.006
t = -1 × 10^-4 × - 0.006
t = 6 × 10^-7 second
So it will take 6 × 10^-7 a for charge to reached 99.99% of it's maximum charge
Explanation:
Formula to determine the critical crack is as follows.
= 1, 
= 24.1
[/tex]\sigma_{y}[/tex] = 570
and, 
= 427.5
Hence, we will calculate the critical crack length as follows.
a = 
= 
= 
Therefore, largest size is as follows.
Largest size = 2a
= 
= 
Thus, we can conclude that the critical crack length for a through crack contained within the given plate is .
