In a perfectly inelastic collision, two spheres made of the same material with masses 15 kg and 25 kg, moving in opposite directions with speeds of 10 m/s and 30 m/s, respectively, strike each other and stick together. The rise in temperature (in ∘C), if all the heat produced during the collision is retained by these spheres, is : (specific heat of sphere material 31cal/kg.∘C and 1cal=4.2 J)
Held on 23 Jan 2026 · Verified 6 Jul 2026.
1.15
1.75
1.44
1.95
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