Answer:
The resistance will be twice the original resistance
Explanation:
This is a fairly simple question, the formular for the resistance of a wire is given as
R = rho *length / area
Where R = resistance
Rho = resistivity
L = length
A = area
Since the density and area are constant I.e they do not change
R/ length = rho/ area
The initial length is given as L, when this length is stretched to twice its original length ,it becomes 2×L = 2L
Let x represent the resistance when the length is doubled
R/ L = x / 2L
x = 2LR / L ; dividing by L
We have that x = 2R ; twice the resistance
Answer:
The heater is not a perpetual motion machine.
Explanation:
A perpetual motion machine is a machine that can run forever without any energy inputs. That is, it delivers the same amount of energy as it uses. Such a machine is almost hypothetical because it is opposite to the second law of thermodynamics.
The heater mentioned in the question is not a perpetual motion machine because it delivers less energy than it requires. It uses 10 kW-h of electricity to produce 9 kW-h of heat according to the question.
<u>Answer:</u>
Total displacement traveled = 298
<u>Explanation:</u>
According to the given information, to actually climb for 1 cm, the caterpillar has to travel for 3 cm (2 cm upwards and 1 cm downwards).
So in order to climb straight up a one meter (100 cm) high wall, it needs to travel for 99 × 3 = 297 cm.
Then after a little it can travel up another cm to reach the top.
Therefore, the total displacement traveled = 297 + 1 = 298 cm
Your question has no context, nobody’s going to be able to answer it.
Answer:
7.5 m/s²
Explanation:
Given:
v₀ = 0 m/s
v = 30 m/s
t = 4 s
Find: a
v = at + v₀
(30 m/s) = a (4 s) + (0 m/s)
a = 7.5 m/s²
