The kinetic energy (k) of an object with mass (m) and speed (v) is given by the formula k = ½ mv². For object x, mass is m and speed is u, so k_x = ½ mu². For object y, mass is m and speed is 3u, so k_y = ½ m(3u)² = ½ m(9u²) = 9 (½ mu²). Comparing k_y with k_x, we find k_y = 9k_x, or 9k_x = k_y.
Two objects, x and y, have equal mass and are moving with speeds u and 3u respectively. Their kinetic energies k_x and k_y are related as
Asked in UPSC CAPF 2022 · Topic: Mechanics (Work, Energy, and Power)
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