Question Number 194600 by byaw last updated on 10/Jul/23
$$ \\ $$An object is pulled up a smooth plane inclined at angle 45° to the horizontal. If the plane is 25 m long and the object comes to rest at the top, correct to two decimal places the:
(i) initial speed of the object
(ii) time taken to reach the top.
Answered by mr W last updated on 14/Jul/23
$$\left(\mathrm{1}\right) \\ $$$${v}_{\mathrm{1}} ^{\mathrm{2}} ={v}_{\mathrm{2}} ^{\mathrm{2}} +\mathrm{2}{gh}=\mathrm{0}+\mathrm{2}×\mathrm{10}×\frac{\mathrm{25}}{\:\sqrt{\mathrm{2}}} \\ $$$$\Rightarrow{v}_{\mathrm{1}} =\mathrm{18}.\mathrm{80}\:{m}/{s} \\ $$$$\left(\mathrm{2}\right) \\ $$$${t}=\frac{\mathrm{2}×\mathrm{25}}{\mathrm{18}.\mathrm{8}}=\mathrm{2}.\mathrm{66}\:{s} \\ $$