Answer:
Thin, aluminium and buried underground.
Explanation:
When it comes to electrification of a state or province, some characteristics of the wire to use must be considered. This would help to minimize and avoid power loss and wire burns.
i. The wire to use should be thin, and a quite number can be twisted one against the other so as to increase the surface area for heat dissipation.
ii. Aluminium wire is more preferable for this project. It has a high melting point, and reduces energy loss.
iii. Burying the wire underground through an insulator is the best choice, though expensive but would preserve the wire from external influence.
A bodybuilder deadlifts 215 kg to a height of 0.90 m. If he deadlifts this weight 10 times in 45 s, the power exerted is 421 W (b.)
<h3>What is power?</h3>
In physics, power (P) is the work (W) done over a period of time.
- Step 1. Calculate the work done by the bodybuilder each time.
The bodybuilder lifts a 215 kg (m) weight to a height of 0.90 m (h). Being the gravity (g) of 9.81 m/s², we can calculate the work done in each lift using the following expression.
W = m × g × h = 215 kg × 9.81 m/s² × 0.90 m = 1.9 × 10³ N
- Step 2. Calculate the work done by the bodybuilder over 10 times.
W = 10 × 1.9 × 10³ N = 1.9 × 10⁴ N
- Step 3. Calculate the power exerted by the bodybuilder.
The bodybuilder does a work of 1.9 × 10⁴ N in a 45-s span.
P = 1.9 × 10⁴ N/45 s = 421 W
A bodybuilder deadlifts 215 kg to a height of 0.90 m. If he deadlifts this weight 10 times in 45 s, the power exerted is 421 W (b.)
Learn more about power here: brainly.com/question/911620
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Answer:
b and d
a, c, e, and f
Explanation:
Ideal gas law:
PV = nRT
Solving for temperature:
T = PV / (nR)
Therefore, temperature is directly proportional to pressure and volume, and inversely proportional to the number of molecules.
T = k PV / N
Let's say that T₀ is the temperature when P = 100 kPa, V = 4 L, and N = 6×10²³.
a) T = k PV / N = T₀
b) T = k (2P) V / N = 2T₀
c) T = k (P/2) (2V) / N = T₀
d) T = k PV / (N/2) = 2T₀
e) T = k P (V/2) / (N/2) = T₀
f) T = k (P/2) V / (N/2) = T₀
b and d have the highest temperature,
a, c, e, and f have the lowest temperature.
<span>So when two metals of equal mass but different heat capabilities are subjected to same heat quantity, the metal with higher heat capacity have the small temperature change. Heat supplied is determined as heat capacity of the metal times the change in temperature.</span>
Answer: W = 1.5 J
Explanation: Work is the product of force and distance. It can be expressed in the following formula W = Fd.
W = Fd
= 5 N ( 0.3 M )
= 1.5 J
