Answer:
The speed of q₂ is 
Explanation:
Given that,
Distance = 0.4 m apart
Suppose, A small metal sphere, carrying a net charge q₁ = −2μC, is held in a stationary position by insulating supports. A second small metal sphere, with a net charge of q₂ = −8μC and mass 1.50g, is projected toward q₁. When the two spheres are 0.800m apart, q₂ is moving toward q₁ with speed 20m/s.
We need to calculate the speed of q₂
Using conservation of energy



Put the value into the formula






Hence, The speed of q₂ is 
Convection is the answer i
think
Answer:
<em>The velocity of the two cars is 10 m/s after the collision.</em>
Explanation:
<u>Law Of Conservation Of Linear Momentum
</u>
The total momentum of a system of bodies is conserved unless an external force is applied to it. The formula for the momentum of a body with mass m and velocity v is
P=m.v
If we have a system of bodies, then the total momentum is the sum of them all

If some collision occurs, the velocities change to v' and the final momentum is:

In a system of two masses, the law of conservation of linear momentum takes the form:

If both masses stick together after the collision at a common speed v', then:

The car of mass m1=1000 Kg travels at v1=25 m/s and collides with another car of m2=1500 Kg which is at rest (v2=0).
Knowing both cars stick and move together after the collision, their velocity is found solving for v':



v' = 10 m/s
The velocity of the two cars is 10 m/s after the collision.
Answer:
Frequency
Explanation:
The property of waves that remains unchanged as it crosses the boundary of one medium to another is the frequency of the wave.
As a wave moves from one boundary to another, the wavelength and the speed of the wave changes.
The speed of the wave is product of wavelength and frequency. Also, the wavelength of the wave is function of the distance between successive crests or troughs of a wave.
The frequency of a wave is the number of waves that crosses a medium per unit of time.