Question 1.
- mass = 4500 kg
- potential energy (p.e) = 67500 J
now, we know :
=》
[tex]p.e = mgh[/tex]
=》
[tex]67500 = 4500 \times 10 \times h[/tex]
=》
[tex]67500 = 45000 \times h[/tex]
=》
[tex]h = \dfrac{67500}{45000} [/tex]
=》
[tex]h = 1.5 \: m[/tex]
note : if we take acceleration due to gravity as 9.8, then height = 1.53 m
Question 2.
- mass = 4500 kg
- kinetic energy = 63000 j
we know,
=》
[tex]k.e = \dfrac{1}{2} mv {}^{2} [/tex]
=》
[tex]63000 = \dfrac{1}{2} \times 4500 \times {v}^{2} [/tex]
=》
[tex] {v}^{2} = \dfrac{63000 \times 2}{4500} [/tex]
=》
[tex] {v}^{2} = 28[/tex]
=》
[tex]v = \sqrt{28} [/tex]
=》
[tex]v = 2 \sqrt{7} \: \: ms {}^{ - 1} [/tex]
or
=》
[tex]5.29 \: \: ms {}^{ - 1} [/tex]
