Question

A student fires a cannonball vertically upwards. The cannonball returns to the
ground after a 4.60s flight. Determine all unknowns and answer the following
questions. Neglect drag and the initial height and horizontal motion of the
cannonball. Use regular metric units (ie. meters).
How long did the cannonball rise?
unit
What was the cannonball's initial speed?
unit
What was the cannonball's maximum height?
unit
V

Answer 1

Answer:

(a). The distance is 207 m.

(b). The initial velocity is 45.0 m/s

(c). The maximum height is 103.3 m

Explanation:

Given that,

Time = 4.60 s

We need to calculate the initial velocity

Using equation of motion

$v=u-gt$

Put the value into the formula

$0=u-9.8\times4.60$

$u=45.0\ m/s$

We need to calculate the distance

Using formula of distance

$d=v\times t$

Put the value into the formula

$d=45\times4.60$

$d=207\ m$

We need to calculate the maximum height

Using equation of motion

$v^2=u^2-2gh$

Put the value into the formula

$0=(45.0)^2-2\times9.8\times h$

$h=\dfrac{(45.0)^2}{2\times9.8}$

$h=103.3\ m$

Hence, (a). The distance is 207 m.

(b). The initial velocity is 45.0 m/s

(c). The maximum height is 103.3 m