EX 18A Electrical Power and Energy

If V is the potential difference, I is the current and R is the resistance, what is the formula for the electrical Power produced, P, in terms of V and I?

• P = V I

• P = V² I

If V is the potential difference, I is the current and R is the resistance, what is the formula for the electrical Power produced, P, in terms of I and R?

• P = I R

• P = I² R

If V is the potential difference, I is the current and R is the resistance, what is the formula for the electrical Power produced, P, in terms of V and R?

• P = V R

• P = V² R

If V is the potential difference, I is the current, R is the resistance and t is the time taken, what is the formula for the electrical energy released, E, in terms of V, I and t?

• E = V I t

• E = V² I t

If V is the potential difference, I is the current, R is the resistance and t is the time taken, what is the formula for the electrical energy released, E, in terms of I, R and t?

• E = I R t

• E = I² R t

If V is the potential difference, I is the current, R is the resistance and t is the time taken, what is the formula for the electrical energy released, E, in terms of V, R and t?

• E = V R t

• E = V² R t

Given a lamp of operating voltage 240 V, power 60 W, what is its operating current I and resistance R? (Hint: use P = V x I and R = V / I)

Given a TV of operating voltage 240 V, operating current 1 A, what is its operating resistance R and power P? (Hint: use P = V x I and R = V / I)

• 240 Ω,

  240 W

An iron of 750 W power is switched on for 30 mins. The energy consumed in kWH is ____ kWh

• 750 x 30

• 750 x 0.5

• 0.75 x 30

• 0.75 x 0.5