Answer:
Cutting down trees instead of growing trees raises levels in the atmosphere, and Using clean energy sources instead of fossil fuels decreases the co2 levels in the atmosphere.
Explanation:
We know that the cutting down of tree and more use of fossil fuels increase the carbon dioxide in atmosphere and we can overcome it by using clean energy sources instead of fossil fuels.
Answer:
Explanation:
The energy stored in a spring
= 1/2 k x²
where k is spring constant and x is extension in the spring.
= .5 x 500 x .05²
= .625 J
Work done by friction = energy dissipated
= - μmg x d , μ is coefficient of friction , m is mass , d is displacement
= - .35 x 2.8 x 9.8 x .05
= - .48 J
energy of the mass when it reaches equilibrium position
= .625 - .48
= .145 J
If v be its velocity at that time
1/2 m v ² = .145
.5 x 2.8 x v² = .145
v² = .10357
v = .32 m /s
32 cm /s
Yes the temp should be changed
Answer:652.05 J
Explanation:
Given
Weight of lifter 
vertical distance move 
Work done in lifting the weight is equal change in Potential Energy of weight
Change in Potential Energy 

therefore work done is equal to