Final answer:
To calculate the amount of charge the battery can provide before it needs recharging, multiply the current by the time. To calculate the energy provided by the battery, use the formula E = Q x V. The battery can provide 18000 joules of energy before it needs recharging.
Step-by-step explanation:
To calculate the amount of charge the battery can provide, we need to multiply the current (in amps) by the time (in seconds). However, we need to convert minutes to seconds first. The battery can supply a current of 5 amps for 20 minutes, which is equivalent to 1200 seconds. So, the amount of charge the battery can provide is 5 A x 1200 s = 6000 C.
To calculate the energy provided by the battery, we can use the formula E = Q x V, where E is the energy (in joules), Q is the charge (in coulombs), and V is the voltage (in volts). Since the voltage is given as 3 volts, the energy provided by the battery is 6000 C x 3 V = 18000 J. Therefore,
the battery can provide 18000 joules of energy before it needs recharging.