Answer:
10 KJ
Explanation:
We are told that 4.0kJ of energy is required to raise the temperature of 1.0kg of paraffin by 2.0°C.
Formula for heat energy here is;
Q = mcΔt
Where;
m is mass
c is specific heat capacity
ΔT is change in temperature
Thus;
4 = 1 × c × 2
c = 4/2
c = 2 Kj/Kg°C
The energy required to raise the temperature of 5.0kg of paraffin by 1.0°C would be;
Q_new = 5 × 2 × 1
Q_new = 10 KJ
Answer:
Option (b).
Explanation:
A star is a heavenly body which emits a tremendous amount of energy by the reaction of nuclear fusion.
Sun is the smallest star in the universe.
The star stars from the proto star, this is the process of birth of a star. Then it collapse due to the gravitational pull and then it tarts emit light and energy and become a star.
After the long long time, it starts to decay and become a neutron star or the black hole.
So, the correct option is (b).
Speed=frequency*wavelength
Given
frequency=1200\ Hz
and
wavelength=0.300\ m
we get:
speed=1200\ Hz*0.300\ m=360\ m/s
Let the mass of the person be m. Total momentum is conserved (because the exterior forces on the system are balanced), especially the component in the vertical direction.
Given that,
Mass of gallon is M
Let man mass be m
Velocity of man is v
Let velocity if ballot be Vb
When the person begin to move we have
Conservation of momentum
mv + MVb=0
MVb=-mv
Vb= -(m/M) v
Given that the mass of man is less than mass of balloon. i.e. m<M
So, if m<M, then, m/M <1
Therefore, .
Vb= -(m/M) v
Vb< -v
This implies that the velocity of balloon is less than the velocity of man and if is also moving in opposite direction
So the man is moving upward, then the balloon is moving downward and it's velocity is less than the velocity of man,
The answer is C
Down with a speed less than v