Answer:
Current, I = 2.3 A
Explanation:
We have,
Voltage of the battery in a circuit is 9 volts
Resistance of the circuit is 4 ohms
It is required to find the current in a circuit. When the voltage and the resistance of the circuit is given then we can find the current in it is given by Ohm's law as :

I is electric current

or
I = 2.3 A
So, the current in the circuit is 2.3 A.
Explanation:
Mass of the ball, m = 0.058 kg
Initial speed of the ball, u = 11 m/s
Final speed of the ball, v = -11 m/s (negative as it rebounds)
Time, t = 2.1 s
(a) Let F is the average force exerted on the wall. It is given by :


F = 0.607 N
(b) Area of wall, 
Let P is the average pressure on that area. It is given by :


P = 0.202 Pa
Hence, this is the required solution.
Answer: A piston-filling fountain pen has a piston — just like in a car — inside the barrel. This piston goes down to expel air or ink and then back up, pulling ink into the barrel. The typical process is very simple, assuming the pen is clean and dry: Push the piston down, expelling any air in the barrel
The primary force would be Thermal Convection, it pushes it and thus makes continents drift.
-Hope that helps, Nexxmexx :3
Answer:
a. blue light
Explanation: hope this helps :)