Answer:
W=1705.2 J
Explanation:
Given that
mass ,m= 60 kg
Acceleration due to gravity ,g= 9.8 m/s²
Height ,h= 2.9 m
As we know that work done by a force given as
W = F . d
F=force
d=Displacement
W=work done by force
Now by putting the values
F= m g (Acting downward )
d= h (Upward)
W= m g h ( work done against the force)
W= 60 x 9.8 x 2.9 J
W=1705.2 J
Therefore the answer will be 1705.2 J.
When an unbalanced force acts on an object the change in the object state of rest or motion depends on the size and direction of the force.
If a body is at state of rest or motion, when an unbalanced external force acts on it, its starts moving in the direction of force and magnitude of its velocity or acceleration depends on the magnitude of force applied.
Answer:
d. 37 °C
Explanation:
= mass of lump of metal = 250 g
= specific heat of lump of metal = 0.25 cal/g°C
= Initial temperature of lump of metal = 70 °C
= mass of water = 75 g
= specific heat of water = 1 cal/g°C
= Initial temperature of water = 20 °C
= mass of calorimeter = 500 g
= specific heat of calorimeter = 0.10 cal/g°C
= Initial temperature of calorimeter = 20 °C
= Final equilibrium temperature
Using conservation of heat
Heat lost by lump of metal = heat gained by water + heat gained by calorimeter

Answer:
She can consider using agricultural waste or dried dung.
Explanation:
No doubt, biomass has become a crucial source of energy to the society, with almost 90% of the households in rural area now relying on biomass for energy. Biomass has become a great option for household heating and cooking. It is locally available and abundant. It is a clean type of fuel, unlike fossil fuels and it somehow helps in cleaning our environment as it traps carbondioxide. Some common types of biomass include dried dung, agricultural waste, or even charcoal.