Answer
given,
Weight of the child = 110 N
length of the swing,L = 2 m
now, calculating the potential energy when the string is horizontal
Potential energy = m g h
now, h = L (1 - cos θ) where θ is the angle made by the string with the vertical.
PE = m g L (1 - cos θ)
when rope is horizontal θ = 90°
PE = 110 x 2 (1 - cos 90°)
PE = 220 J
now, calculating potential energy when string made 25° with horizontal
PE = m g L (1 - cos θ)
when rope is horizontal θ = 25°
PE = 110 x 2 (1 - cos 25°)
PE = 20.61 J
The speed will increase four (4) times when the frequency of sound wave is increased four (4) times.
<h3>How to calculate the
frequency of a
wave.</h3>
Mathematically, the frequency of a sound wave is given by this formula:

<u>Where:</u>
- F is the frequency of a sound wave.
- V is the velocity of a sound wave.
is the wavelength of a sound wave.
<u>Note:</u> The frequency of the sound wave is increased four (4) times.
Substituting the given parameters into the formula, we have;

Therefore, the speed will increase four (4) times when the frequency of sound wave is increased four (4) times.
Read more on sound wave here: brainly.com/question/19250621
Answer:
602.27 kg
Explanation:
The computation of the largest mass of cargo the balloon can lift is shown below:-
Volume of helium inside the ballon= (4 ÷ 3) × π × r^3
= (4 ÷ 3) × 3.14 × 6.953
= 1406.19 m3
Mass the balloon can carry = volume × (density of air-density of helium)
= 1406.19 × (1.29-0.179)
= 1562.27 kg
Mass of cargo it can carry = Mass it can carry - Mass of structure
= 1562.27 - 960
= 602.27 kg
Answer: Blood primarily moves in the veins by the rhythmic movement of smooth muscle in the vessel wall and by the action of the skeletal muscle as the body moves. Because most veins must move blood against the pull of gravity, blood is prevented from flowing backward in the veins by one-way valves.
Good luck !