P=IV
V=IR
P=I(IR)
P=I²R
375=5²R
R=375/25
R=15
Answer: 40 Newton
Explanation:
Mass of baseball = 20 kg
Velocity of baseball = 20 m/s.
Time taken for throwing = 10 seconds
Since acceleration is the rate of change of velocity per unit time
i.e Acceleration = velocity / time taken
Acceleration = (20 m/s / 10seconds)
Acceleration = 2m/s^2
Now, force required to throw the baseball is a product of mass and acceleration
i.e Force = Mass x acceleration
Force = 20 kg x 2m/s^2
Force = 40Newton
Thus, 40 newton of force is required to throw baseball to reach the plate
Answer:
The voltage on the secondary is 12 V while the current is 0.5 A.
Explanation:
A transformer works by changing the level of the voltage and current on a circuit using a magnetic field and two coils. The ratio by wich they are changed is dependant on the ratio of turns between the primary and secondary of the transformer. In this case we have a ratio for the voltage of:
ratio = (turns on the secondary)/(turns on the primary)
ratio = 100/1000 = 0.1
So in this case the voltage delivered to the primary will be multiplied by 0.1. We can now calculate the voltage on the secondary:
Voltage secondary = Voltage primary* ratio = 120*0.1 = 12 V
The transformer maintains roughly the same power output on both sides, since the power output on a electric circuit is given by the product of the voltage by the current on that circuit, to maintain the same power when the voltage has been droped the current must be raised by the same ratio. So we have:
Current secondary = Current primary*(1/ratio) =0.05*(1/0.1) = 0.5 A
Answer:
C. Blueshift
"If a star is moving towards the earth, its light is shifted to higher frequencies on the color spectrum (towards the green/blue/violet/ultraviolet/x-ray/gamma-ray end of the spectrum). A higher frequency shift is called a "blue shift"
Source: http://wtamu.edu/~cbaird/sq/2013/06/27/have-astronomers-ever-observed-a-violet-shift-like-they-have-blue-shifts-and-red-shifts/
