Answer:
A
Explanation:
Resistors in series add. There is only one path the current can take. That's why Christmas Tree lights sometimes give a lot of trouble. If a bulb burns out, it could be any one of them and time is needed to find the burned out bulb.
That being the case R = R1 + R2
R1 = 50 ohms
R2 = 50 ohms
R = 50 + 50
R = 100 ohms
Answer A
Suppose you are doing an experiment where you determine the value of one parameter, say density of a liquid. You have two methods in doing this. By finding the mass and volume, and by using a densitometer. Reproducibility is when you get the same value of density for both methods. Replicability is when you have similar results in one method. So, replicability is a measure of precision, while reproducibility is a measure of accuracy.
The correct answer to the question is : 9375 N.
CALCULATION:
As per the question, the mass of the car m = 1500 Kg.
The diametre of the circular track D = 200 m.
Hence, the radius of the circular path R = 
= 
= 100 m.
The velocity of the truck v = 25 m/s.
When a body moves in a circular path, the body needs a centripetal force which helps the body stick to the orbit. It acts along the radius and towards the centre.
Hence, the force acting on the car is centripetal force.
The magnitude of the centripetal force is calculated as -
Force F = 
= 
= 9375 N. [ANS}
The centripetal force is provided to the car in two ways. It is the friction which provides the necessary centripetal force. Sometimes friction is not sufficient. At that time, the road is banked to some extent which provides the necessary centripetal force.
Using conservation of energy law:-
∑ work in = ∑ work out
and work= force* displacement
so when we wanted to move a 100kg a distance of 1m
we multiplied 100*1 = work out
so work in should be equal to 100*g Joules, where g is the acceleration due to gravity.
so workout = 100*g = 25*g *x (divide both sides by 25*g)
x=4m
by the same way:-
------------------------
work in = 100kg * 2m * g (m/

)= work out
so work out = 25*x*g = 200* g (divide both sides by 25*g)
x=8m
I think the correct answer from the choices listed above would be the last option. It is the chemicals in the core of the star that cannot be determined from the spectrum of a star. Spectrum shows the different classification of the stars depending on their spectral characteristics. It usually involves the light, the wavelength and the distance.