iran-konkur 2023 Q42

iran-konkur · Other · konkur-riazi_1402_tir_specialized Constant acceleration (SUVAT) Vertical projection from ground level
42. A bullet is fired vertically upward from the Earth's surface and reaches a height of 42 meters above the Earth's surface, and its kinetic energy decreases by 30\%. What is the maximum height (in meters) this bullet reaches above the Earth's surface?
(air resistance is negligible and $g = 10\,\dfrac{\mathrm{m}}{\mathrm{s}^2}$)
(1) 96 (2) 120 (3) 140 (4) 149
\noindent\textbf{42.} A bullet is fired vertically upward from the Earth's surface and reaches a height of 42 meters above the Earth's surface, and its kinetic energy decreases by 30\%. What is the maximum height (in meters) this bullet reaches above the Earth's surface?

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\noindent (air resistance is negligible and $g = 10\,\dfrac{\mathrm{m}}{\mathrm{s}^2}$)

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\noindent (1) 96 \hfill (2) 120 \hfill (3) 140 \hfill (4) 149

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