An 80 kg person is parachuting and is experiencing a downward acceleration of `"2.8 m s"^(-2)`. The mass of the parachute is 5 kg. If the upward force on the open parachute is `kxx10^(2)N`, then what is the value of k? `("Take "g=9.8ms^(-2))`

Answer

5.95

Explanation

Mass of the person M = 80 kg
Mass of the parachute m = 5 kg
`:.` Total mass of the system = M +m = 85kg
Downward acceleration a = 2.8 `ms^(- 2)`
Let upward force = F
Applying Newton.s II law of motion to this system
F= (m + M)g - (m + M)a
or F = ( m + M) (g - a)
F = 85 (9.8 - 2.8)N
`= 85 xx 7` N
`F = 595 N = 5.95 xx 10^(2) N`
k = 5.95