Let M = mass of the skier,
v2 = his speed at the end of the track.
By conservation of energy,
1/2 Mv^2 = 1/2 Mv2^2 + Mgh
Dividing by M,
1/2 v^2 = 1/2 v2^2 + gh
Multiplying by 2,
v^2 = v2^2 + 2gh
Or v2^2 = v^2 - 2gh
Or v2^2 = 4.8^2 - 2 * 9.8 * 0.46
Or v2^2 = 23.04 - 9.016
Or v2^2 = 14.024 m^2/s^2-----------------------------(1)
In projectile motion, launch speed = v2
and launch angle theta = 48 deg
Maximum height
H = v2^2 sin^2(theta)/(2g)
Substituting theta = 48 deg and value of v2^2 from (1),
H = 14.024 * sin^2(48 deg)/(2 * 9.8)
Or H = 14.024 * 0.7431^2/19.6
Or H = 14.024 * 0.5523/19.6
Or H = 0.395 m = 0.4 m after rounding off
Ans: 0.4 m
The answer in this question is 0.4 m
<h3><u>Question</u><u>:</u></h3>
A racing car is travelling at 70 m/s and accelerates at -14 m/s^2. What would the car’s speed be after 3 s?
<h3><u>Statement:</u></h3>
A racing car is travelling at 70 m/s and accelerates at -14 m/s^2.
<h3><u>Solution</u><u>:</u></h3>
- Initial velocity (u) = 70 m/s
- Acceleration (a) = -14 m/s^2
- Time (t) = 3 s
- Let the velocity of the car after 3 s be v m/s
- By using the formula,
v = u + at, we have

- So, the velocity of the car after 3 s is 28 m/s.
<h3><u>Answer:</u></h3>
The car's speed after 3 s is 28 m/s.
Hope it helps
Answer:
Her computer is producing thermal energy, not heat.
Explanation:
Answer:
The new current in the straight wire is 4.98 A
Explanation:
Given;
initial magnetic force on the wire, F₁ = 0.017 N
initial current flowing on the straight wire, I₁ = 1.1 A
When the current in the wire is changed,
new magnetic force on the wire, F₂ = 0.077 N
the new current in the wire, I₂ = ?
Applying equation of magnetic force on conductor;
F₁ = I₁BLsinθ
F₂ = I₂BLsinθ
BLsinθ = F₁/I₁ = F₂/I₂
I₂ = (F₂I₁)/F₁
I₂ = (0.077 x 1.1) / 0.017
I₂ = 4.98 A
Therefore, the new current in the straight wire is 4.98 A
Answer:
The water releases energy which causes the water molecules to have less kinetic and potential energy, changing their configuration from liquid to solid.
Explanation:
The conversion of water to ice is a phase change from liquid to solid. There is no chemical action taking place in this process just the state of matter taking up a new form.
- This phase change is called freezing.
- In freezing, the liquid water loses energy to the surroundings.
- By so doing, the water molecules have lesser energy
- The then take up fixed position within the lattice.
- This changes the state to solid with a well - ordered arrangement.