(a). The power of the candy bar is,
The time taken to play on 800 kJ energy of the candy bar is,
where E is the energy.
Substituting the known values,
As 1 minute is equal to 60 seconds,
Thus,
Thus, the time taken to play tennis on the 800 kJ energy is 30.3 minutes.
(b). By doing the exercise, the process of digestion of food inside our body increases. Thus, the exercise does not helps us to burn the calories. But it helps us to diggest the heavy meal like candy bar easily.
The time taken to digest the canndy bar or to utilise its energy is large because it takes a lot of time to burn small amount of food and make it digest quickly.
Answer:
Explanation:
The pressure of a liquid is the rate of the force applied by the liquid on a surface per unit area of the surface.
i.e P = 
where P is the pressure, F is the force and A is the area.
The depth of the liquid determines its pressure at a definite lower point. As the pressure of a liquid at the bottom of a its container is greater than the pressure at the top of the liquid.
Thus,
P = σhg
where P is the pressure, σ is the density of the liquid, h is the height and g is the force of gravity.
It is measured in Pascals or N
.
The pressure of liquid has a lot of applications, viz: siphon, force pump, lift pump etc.
Answer:
Explanation:
Let the tension in the cord be T₁ and T₂ .
for motion of block placed on horizontal table
T₁ = m a , a is acceleration of the whole system .
for motion of hanging bucket of mass m
mg - T₂ = ma
adding the two equation
mg + T₁- T₂ = 2ma
for rotational motion of the pulley
torque = moment of inertia x angular acceleration
(T₂ - T₁) R = I x α , I is moment of inertia of pulley , α is angular acceleration .
(mg - 2ma ) R = I x α
(mg - 2ma ) R = I x a / R
(mg - 2ma ) R² = I x a
mgR² = 2ma R² + I x a
a = mgR² / (2m R² + I )
Since body moves by distance d in time T
d = 1/2 a T²
a = 2d / T²
mgR² / (2m R² + I ) = 2d / T²
mgR²T² = 2d x (2m R² + I )
mgR²T² - 4dm R² = 2dI
m R² ( gT² - 4d ) = 2dI
I = m R² ( gT² - 4d ) ] / 2d .
Answer:The percentage of the work input that becomes work output is the efficiency of a machine. Because there is always some friction, the efficiency of any machine is always less than 100 percent.
Explanation:
Sub to rockingcoolstyle15 on yt
