Answer:
=170kcal
Explanation:
We first calculate the amount of energy required to melt the alcohol using the formula: MLf, where Lf is the latent heat of fussion
We then calculate amount of heat required to raise the temperature of liquid alcohol to -14° C using MC∅. We then add the two.
Thus ΔH=MLf+MC∅
ΔH=2kg×25kcal/kg+ 2kg×(0.6kcal/kg.K×(-14-⁻114)
=50kcal+120kcal
=170kcal
Answer:
A star uses fusion as an energy source by building larger atoms from smaller atoms.
Explanation:
Nuclear fission and fusion are two processes at which an atomic nucleus is changed to produce energy. Fission is the process splitting heavy atomic into lighter atomic nuclei.
So, fusion is the combination of smaller atoms to form larger atoms and star uses this as source of energy.
Fusion is the process at which light atomic nuclei are merged or fused together to form heavier nuclei.
The energy source for all stars is nuclear fusion. In a nuclear fusion reaction, the nuclei of two atoms combine to create a new atom. Most commonly, in the core of a star, two hydrogen atoms fuse to become a helium atom.
Answer: The correct answer for the blank is- a. change its position relative to other objects.
Perception of motion can be described as a phenomenon of inferring the direction and speed and of objects, which are moving in a visual scene.
An object is said to be in motion if its position is changed with respect to objects that are present in its surrounding.
Thus, in order to sense motion of objects, humans beings are required to see an object change its position with respect to other objects.
Weight is equivalent to the product of the mass of an object and the strength of the gravitational field.
Using:
F = ma
a = 8.2 / 5
a = 1.64 N/kg
The gravitational field strength is equivalent to 1.64 N/kg.
Answer:
Explanation:
A.
Given:
Vo = 21 m/s
Vf = 0 m/s
Using equation of Motion,
Vf^2 = Vo^2 - 2aS
S = (21^2)/2 × 9.8
= 22.5 m.
B.
Given:
S = 22.5 + 21 mm
= 22.521 m
Vo = 0 m/s
Using the equation of motion,
S = Vo × t + 1/2 × a × t^2
22.521 = 0 + 1/2 × 9.8 × t^2
t^2 = (2 × 22.521)/9.8
= 4.6
t = 2.14 s