Answer:
Only main sequence stars have a well-defined relationship between spectral type and luminosity.
Explanation:
Low-mass stars have much longer lifetimes than high-mass stars.
Answer:
<em>0.97c</em>
<em></em>
Explanation:
From the relativistic equation for length contraction, we have
= 
where
is the final length of the object
is the original length of the object before contraction
β = 
where v is the speed of the object
c is the speed of light in free space = 3 x 10^8 m/s
The equation can be re-written as
/
= 
For the length to contract to one-fourth of the proper length, then
/
= 1/4
substituting into the equation, we'll have
1/4 = 
substituting for β, we'll have
1/4 = 
squaring both side of the equation, we'll have
1/16 = 1 - 
= 1 - 1/16
= 15/16
square root both sides of the equation, we have
v/c = 0.968
v = <em>0.97c</em>
A force field works the same as a shield. I protects what ever is inside, or behind the field.
Magnitude 17 root
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Answer:
D- component of the gravitational force parallel to the plane increased and normal force exerted by the board decreased
Explanation:
component of the gravitational force parallel to the plane = mg sinθ ; where θ is inclination of the plane . As it increases , sinθ increases and hence component of the gravitational force parallel to the plane increases .
normal force exerted by the board = mg cosθ . As θ increases , cosθ decreases and hence normal force exerted by the board decreases and hence friction force decreases because
Friction force = coefficient of friction x normal force exerted by the board .
coefficient of friction remains constant.