The car is traveling at v=12m/s. Kinetic energy is given by this formula:
We can see that if the kinetic energy depends on the speed quadratically. This means that if you want to increase the kinetic energy x times you would have to increase speed
times. We conclude from this that car would have to go:
Answer:
dynamic and sometimes ballistic
knowledge of first aid ... eg St John Ambulance, Red Cross etc. I think that everyone in a school should be taught First Aid.
Answer:
s₁ = 4.67 m from car A
Explanation:
Since, the cars are moving at a constant speed. Hence, we will apply the equation for uniform motion here:
s = vt
where,
s = distance covered
v = velocity
t = time taken
For Car A:
s₁ = (1.4 m/s)t
For Car B:
s₂ = (2.2 m/s)t
Because the time will be same at the collision. At collision the distance covered by Car A and Car B must be 12 m altogether. Hence:
s₁ + s₂ = 12 m
using values:
(1.4 m/s)t + (2.2 m/s)t = 12 m
t = 12 m/3.6 m/s
t = 3.333 s
Substitute this in the equation of s₁:
s₁ = (1.4 m/s)(3.33 s)
<u>s₁ = 4.67 m from car A</u>
Answer: a) 5 x 10^5 kg/s b) 444 MW
Explanation:
Kinetic energy per unit mass Ke is
Ke = V^2 / 2
Ke = 3^2 / 2 = 4.5 J/kg = 0.0045 kJ/kg
Now potential energy per unit mass Pe is
Pe = g x z = 9.8 x 90 = 882.9 J/kg = 0.8829 kJ/kg
The total mechanical energy of the River per unit mass e = Ke + Pe = 0.0045 + 0.8829 = 0.88744 J/kg
M = P x V = 1000 x 500 = 5 x 10^5 kg/s
b) power generation potential of the entire river at the location Wmax = Emech = M x Emech = 500,000 x 0.88744 = 444,000kW = 444MW
