A 12-V battery is connected to a device and 24 mA (24 x 10' Amps) of current flows
through it. If the device obeys Ohm's law, how much current will flow when a 24-V battery
is used?

Correct  Ic₂ = 48 mA = 48 · 10⁻³ A

Explanation:

Given:

U₁ = 12 V  DC  first battery voltage

Ic₁ = 24 mA = 24 · 10⁻³ A   Intensity of current with the first battery

U₂ = 24 V DC    second battery voltage

Ic₂ = ?   Intensity of current with the second battery

The formula that applies to a simple electric circuit under the Ohm's law is:

R = U / Ic  

where R is the total resistance in the electrical circuit and it is constant.

R = U₁ / Ic₁ = U₂ / Ic₂ ⇒ U₁ / Ic₁ = U₂ / Ic₂  ⇒ Ic₂ = (U₂ · Ic₁) / U₁

Ic₂ = (24 · 24) / 12 = 48 mA

Ic₂ = 48 mA = 48 · 10⁻³ A

God is with you!!!

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.