The voltage on a capacitor decays according to the equation V_{t} = 12.00×e^{- 0.26×t} volts Calculate the voltage, V_{t}, (to 2 dp) when t = 0.6 s.

1.71 volts

5.55 volts

9.63 volts

10.27 volts

Calculate the value of k (to 2 dp) in the equation 1.6×10^{5} = 8.3×10^{6}× e^{2.5×k}

20.75

- 1.58

- 0.69

0.69

The activity of a radioactive isotope as a function of time, t, is described by the equation A_{t} = A_{o}×e^{- 0.693×t/T1/2} If the half life, T_{1/2} = 2.5 years, how long (to 1 dp) will it take for the activity to fall to one hundredth of its initial value.

6.6 years

7.2 years

16.6 years

125.0 years

A population grows exponentially from 2000 to 3000 after a time, t = 2.0 years. Assuming the same growth, calculate the time (to 1 dp) taken for the population to grow from 3000 to 4000.

1.4 years

1.6 years

2.0 years

None of the above

Rearrange the equation N_{t} = N_{0}×e^{k×t} to make t the subject of the equation.