Answer:
D
Explanation:
D) The overall work done by gravity is zero
This statement is correct .
If m be the mass of each of the children and h be the height of tower
work done by gravity on the boys in going up = - mgh
it is so because force applied by gravity = mg downwards and displacement
is upwards
work done will be negative = - mgh
Work done by gravity on boys when they come down = + mgh because both force and displacement are downwards .
Hence total work done = - mgh + mgh = 0.
The children will have same kinetic energy as the inclined surface is friction-less so no energy will be dissipated hence addition of energy to boys in both the cases will be same.
The crate is in equilibrium. Newton's second law gives
∑ <em>F</em> (vertical) = <em>n</em> - <em>mg</em> = 0
∑ <em>F</em> (horizontal) = <em>p</em> - <em>f</em> = 0
where
• <em>n</em> = magnitude of the normal force
• <em>mg</em> = weight of the crate
• <em>p</em> = mag. of push exerted by movers
• <em>f</em> = mag. of kinetic friciton, with <em>f</em> = 0.60<em>n</em>
<em />
It follows that
<em>p</em> = <em>f</em> = 0.60<em>mg</em> = 0.60 (43.0 kg) <em>g</em> = 252.84 N
so that the movers perform
<em>W</em> = <em>p</em> (10.4 m) ≈ 2600 J
of work on the crate. (The <em>total</em> work done on the crate, on the other hand, is zero because the net force on the crate is zero.)
The volume of water in the larger balloon is 8 times greater than in the smaller balloon
We'll begin by calculating the volume of each balloon.
<h3>For smaller balloon:</h3>
- Radius (r) = 3 cm
- Pi (π) = 3.14
- Volume (V) =?
V = 4/3 πr³
V = 4/3 × 3.14 × 3³
<h3>V = 113.04 cm³</h3>
<h3>For larger balloon:</h3>
- Radius (r) = 6 cm
- Pi (π) = 3.14
- Volume (V) =?
V = 4/3 πr³
V = 4/3 × 3.14 × 6³
<h3>V = 904.32 cm³</h3>
Finally, we shall determine how much greater the larger balloon is to the smaller balloon
- Volume of smaller balloon = 113.04 cm³
- Volume of larger balloon = 904.32 cm³
- Greatness =?
Greatness => large / small
Large / small = 904.32 / 113.04
Large / small = 8
Cross multiply
<h3>Large = 8 × small </h3>
Therefore, the larger balloon is 8 times greater than the smaller balloon.
Learn more on volume of sphere: brainly.com/question/9178703
Answer:
600 KPa.
Explanation:
From the question given above, the following data were obtained:
Initial volume (V1) = 0.075 m³
Final volume (V2) = 0.45 m³
Final pressure (P2) = 100 KPa
Initial pressure (P1) =?
Temperature = constant
The initial pressure can be obtained by using the Boyle's law equation as shown below:
P1V1 = P2V2
P1 × 0.075 = 100 × 0.45
P1 × 0.075 = 45
Divide both side by 0.075
P1 = 45 / 0.075
P1 = 600 KPa.
Thus, the initial pressure in the balloon is 600 KPa.
Answer:
speed cannot be used to calculate the temperature
