Question 25 I point
5.0g of water at 25°C is dropped onto a large block of ice at 0°C. The water cools to 0°C and
some of the ice melts.
Assume that all the energy lost by the water is gained by the ice.
What is the mass of ice that melts?
The specific heat capacity of water is 4.2J/(g°C).
The specific latent heat of fusion of ice is 340J/g.
A 0.0629
B 0.0879
C 1.59
D 10g
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Initial velocity,  u = 4.9 m/sfinal velocity = v m/sinitial height,  h₁ =  245 m    final height, h₂ = 0a = -9.8  m/s²time taken = t secondss = ut + 0.5at²⇒  (h₂-h₁) = ut + 0.5at²⇒  0-245 = 4.9t + 0.5×(-9.8)×t²⇒ -245 = 4.9t - 4.9t²⇒ 4.9t² -4.9t -245 =0solving it, we get   t = 7.59sv  = u +  at = 4.9 -9.8×7.59 = 4.9 - 74.38 = -69.48 m/svelocity is  69.48 m/s downward

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