Answer:
B. +5.75 m/s
Explanation:
When there are two bodies, a and b, whose velocities measured by a third observer (in this case, the ground) are and
respectively, the relative velocity of B with respect to A is given by:
Thus, the velocity of the girl relative to the lawnmower is:
Answer:
3°C
Explanation:
We can that heat Q=m dT
Where m is the mass = specific heat capacity
dT = Temperature difference
here we have given m=625 g =.625 kg
specific heat of granite =0.79 J/(g-K) = 0.79 KJ/(kg-k)
=25°C
we have to find
we have also given Q=10.9 KJ
10.9=0.625×0.79×(25-)
25- =22
=3°C