Answer:
a)the process by which heat or electricity is directly transmitted through the material of a substance when there is a difference of temperature
b)the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat
c)radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium.
Answer:
1281.4 J
Explanation:
F = 298 N
d = 4.3 m
the work done is defined as the product of force applied in the direction of displacement and the displacement.
W = force x displacement
Work is a scalar quantity and its SI unit is Joule.
W = F x d
W = 298 x 4.3 = 1281.4 J
Answer:
275 kJ
Explanation:
KE = ½mv² = ½(1200)(25²) = 375,000
<h2>
Answer:</h2>
400N/m
<h2>
Explanation:</h2>
When n identical springs of stiffness k, are attached in series, the reciprocal of their equivalent stiffness (1 / m) is given by the sum of the reciprocal of their individual stiffnesses. i.e
= ∑ⁿ₁ [] -----------------------(i)
That is;
= + + + . . . + -------------------(ii)
If they have the same value of stiffness say s, then equation (ii) becomes;
= n x -----------------(iii)
Where;
n = number of springs
From the question,
There are 3 identical springs, each with stiffness of 1200N/m and they are attached in series. This implies that;
n = 3
s = 1200N/m
Now, to calculate the effective stiffness,m, (i.e the stiffness of a longer spring formed from the series combination of these springs), we substitute these values into equation (iii) above as follows;
= 3 x
=
=
Cross multiply;
m = 400N/m
Therefore, the stiffness of the longer spring is 400N/m