Answer:
0.6 m/s
Explanation:
The details of the masses and velocities are;
The mass of the ice skater, m₁ = 80 kg
The mass of the ball, m₂ = 8 kg
The speed with which the skater tosses the ball forward, v₂ = 6 m/s
Therefore;
According to the principle of conservation of linear momentum, we have;
m₁·v₁ = m₂·v₂
Where;
v₁ = The skater's reactive velocity
Therefore, we get;
80 kg × v₁ = 8 kg × 6 m/s
v₁ = 8 kg × 6 m/s/(80 kg) = 0.6 m/s
The skater's reactive velocity, v₁ = 0.6 m/s.
<span> 1) When light is passing from a denser medium to a lighter medium ( for eg: from water to air)
2) When the angle of refraction is greater than the critical angle( angle of incidence when the angle of refraction is perpendicular to the normal) of the denser medium. </span>
Answer:
<h2>36 km</h2>
Explanation:
The distance covered by an object given it's velocity and time taken can be found by using the formula
distance = velocity × time
From the question we have
distance = 18 × 2
We have the final answer as
<h3>36 km</h3>
Hope this helps you
Answer:
A= 150 J
Explanation:
Kinetic energy is the energy of an object in motion.
The formula for kinetic energy is ;
K.E = 1/2 * m *v² where m is mass and v is velocity
Work done is equal to change in kinetic energy
W= Δ K.E
Given that K.E = 150 J
Taking that the ball was stationary before it was thrown, this makes its initial kinetic energy to be 0 J so the work done will be
W= Δ K.E
W= 150 - 0
W= 150 J
The ducks' flight path as observed by someone standing on the ground is the sum of the wind velocity and the ducks' velocity relative to the wind:
ducks (relative to wind) + wind (relative to Earth) = ducks (relative to Earth)
or equivalently,

(see the attached graphic)
We have
- ducks (relative to wind) = 7.0 m/s in some direction <em>θ</em> relative to the positive horizontal direction, or

- wind (relative to Earth) = 5.0 m/s due East, or

- ducks (relative to earth) = some speed <em>v</em> due South, or

Then by setting components equal, we have


We only care about the direction for this question, which we get from the first equation:



or approximately 136º or 224º.
Only one of these directions must be correct. Choosing between them is a matter of picking the one that satisfies <em>both</em> equations. We want

which means <em>θ</em> must be between 180º and 360º (since angles in this range have negative sine).
So the ducks must fly (relative to the air) in a direction 224º relative to the positive horizontal direction, or about 44º South of West.