To solve the problem, we must use the following equation:

where
Q is the amount of heat energy absorbed by the water
m is the mass of the water
Ti and Tf are the initial and final temperature
Cs is the specific heat capacity of the water
The data we have in this problem are:
Q=40.0 kJ


m=0.500 kg
Substituting the data into the equation and re-arranging it, we find

So the final temperature of the water will be 29.1 degrees.
Answer:
3. relatively high temperature, about 10,000 K, so that significant numbers of electrons are excited from the ground state, n = 1, to the first excited state, n = 2, but not too many of them have been ejected completely from the atoms
Explanation:
If hydrogen absorption lines are very strong in the visible spectrum of a particular star that means the population of electron in n = 2 is very high so on being exited they absorb radiation in Balmer series and give rise to absorption spectrum. The average temperature required to excite electron in hydrogen atom from n=1 to n = 2 is 10000K .
Answer:
v = 34.128 km/hr
Explanation:
Given that,
The initial speed of a truck, u = 0
Acceleration of the truck, a = 0.3 m/s²
Distance moved, d = 150 m
Let the final speed of the truck is v. Using third equation of motion i.e.

Put all the values,

or
v = 34.128 km/h
So, the final speed of the truck is equal to 34.128 km/h.