Question

Question #dc78c

Answer 1

Part (a)=332.346m
Part (b)=294.6m
Part (c)=27.2m/s downwards
Part (d)=9.46s

Explanation:

Displacement in m (S) = ?
Initial Velocity in m/s (U) = 12
Final Velocity in m/s (V) = 0 (Not moving at maximum high)
Acceleration in m/s (A) = -9.8 (gravity)
Time in s (T) =

`v^2`=`u^2`+2as

`0=144+2*-9.8*s`
`-144=2*-9.8*s`

s= 7.3469387755m
s+325 for initial height.
332.3469387755m above ground.

Part b
Displacement in m (S) = ?
Initial Velocity in m/s (U) = 12
Final Velocity in m/s (V) =
Acceleration in m/s (A) = -9.8 (gravity)
Time in s (T) = 4

`s=ut+0.5at^2`
`s=12*4+0.5*-9.8*16`
s=-30.4
Add initial height = 294.6m

Part c
Displacement in m (S) =
Initial Velocity in m/s (U) = 12
Final Velocity in m/s (V) = ?
Acceleration in m/s (A) = -9.8 (gravity)
Time in s (T) = 4

`v=u+at`
`?=12+(-9.8)*4`
v=27.2 downwards

Part d
Displacement in m (S) = 294.6
Initial Velocity in m/s (U) = 27.2
Final Velocity in m/s (V) =
Acceleration in m/s (A) = -9.8 (gravity)
Time in s (T) = ?

`s=ut+0.5at^2`
`294.6=27.2*t+0.5*9.8*t`
t=5.46
Add the 4 seconds taken to get to 294.6m = 9.46s

Pretty sure those calculations are correct. Apologies for any errors but the working can be followed to fix any problems.