Answer:
461.88 N
Explanation:
= Weight of the swing = 800 N
= Tension force in the rope
= Horizontal force being applied by the partner
Using equilibrium of force in vertical direction using the force diagram, we get

Using equilibrium of force in horizontal direction using the force diagram, we get

Correct ones are
- Technical improvements that have made alternative energy sources more practical to use
- Increase in concern for environment.
why?
Fossil fuels are hydrocarbons
- Hydrocarbons on burning with oxygen releases harmful carbon dioxide .
Answer:
T = 2 T₀
Explanation:
To answer this question let's write the expression for electrical conductivity
σ = n e2 τ / m*
The relationship with resistivity is
ρ = 1 /σ
Whereby the resistance
R = ρ L / A = 1 /σ L / A
We see that there is no explicit relationship between time and resistance, there is only a dependence on the life time (τ) that depends on the properties of the material, not on its diameter or length.
As also the average velocity or electron velocity of electrons is constant, the time to cross 2 mm in length is twice as long as the time to cross a mm in length
T = 2 T₀
Answer:
117.72kW
Explanation:
Given data
Mass m= 50kg
height x = 2m
time taken = 2 minutes= 129 seconds
let us find the work done
WD= force * distance
WD= mgx
WD= 50*9.81*2
WD= 981 Joules
Let us find the power
Power= work * time
Power= 981*120
Power= 117720
Power= 117.72 kW
Hence the power spent is 117.72kW