Answer:
9.6m/s
Explanation:
Using the equation S=d/t where s=speed, d=distance, and t=time
plug in the known variables
S=120m/12.5s
S=9.6m/s
Answer:
3.38 m/s
Explanation:
Mass of child = m₁ = 25
Initial speed of child = u₁ = 5 m/s
Initial speed of cart = u₂ = 0 m/s
Mass of cart = m₂ = 12 kg
Velocity of cart with child on top = v
This is a case of perfectly inelastic collision

Velocity of cart with child on top is 3.38 m/s
Given parameters:
Mass of the car = 1000kg
Unknown:
Height = ?
To find the heights for the different amount potential energy given, we need to understand what potential energy is.
Potential energy is the energy at rest due to the position of a body.
It is mathematically expressed as:
P.E = mgh
m is the mass
g is the acceleration due to gravity = 9.8m/s²
h is the height of the car
Now the unknown is h, height and we make it the subject of the expression to make for easy calculation.
h = 
<u>For 2.0 x 10³ J;</u>
h =
= 0.204m
<u>For 2.0 x 10⁵ J;</u>
h =
= 20.4m
<u>For 1.0kJ = 1 x 10³J; </u>
h =
= 0.102m
Answer:
the velocity is 10 m/s
Explanation:
Using the expression for kinetic energy we have:
![Ek=\frac{1}{2} *m*v^{2} \\\\Ek=100J\\m=2kg\\v=\sqrt{(2*100/2)}\\ v=10[m/s]](https://tex.z-dn.net/?f=Ek%3D%5Cfrac%7B1%7D%7B2%7D%20%2Am%2Av%5E%7B2%7D%20%5C%5C%5C%5CEk%3D100J%5C%5Cm%3D2kg%5C%5Cv%3D%5Csqrt%7B%282%2A100%2F2%29%7D%5C%5C%20v%3D10%5Bm%2Fs%5D)
Answer:
e = Δφ / Δt induced emf is proportional to enclosed flux
Also φ = B * A flux is proportional to area and enclosed field
If the induced emf e increases with time than the flux and hence the magnetic field is increasing with time (replace B with G)
Since e = ΔG * A / Δt if e is linear then G must also be linear and be proportional to the time