Answer:
In an elastic collision, the total kinetic energy is conserved, while in an inelastic collision, it is not
Explanation:
Let's define the two types of collision:
- Elastic collision: an elastic collision is a collision in which:
1) the total momentum of the system is conserved
2) the total kinetic energy of the system is conserved
Typically, elastic collisions occur when there are no frictional forces acting on the objects in the system, so that no kinetic energy is lost into thermal energy. An example of elastic collision is the collision between biliard balls.
- Inelastic collision: an inelastic collision is a collision in which:
1 ) the total momentum of the system is conserved
2) the total kinetic energy of the system is NOT conserved
In an elastic collision, part of the total kinetic energy is lost (=converted into thermal energy) due to the presence of frictional forces. An example of inelastic collision is the accident between two cars, in which part of the energy is converted into heat.
An example would be gravity
Momentum = mass x velocity
Thus Option A is the correct answer
Momentum (dog) = 10 kg x (0.447 x 30) m/s
= 134.1 Kg m/s
Momentum ( bullet) = 0.02 kg x (0.447 x 800) m/s
= 7.152 Kg m/s
Momentum ( truck) = 0, as v = 0
tightrope has both low mass and low speed, thus its momentum will be low
Answer:
She must stop the car before interception, distance traveled 12.66 m
Explanation:
We will take all units to the SI system
Vo = 48Km / h (1000m / 1Km) (1h / 3600s) = 13.33 m / s
V2 = 70 Km / h = 19.44 m / s
We calculate the distance traveled before stopping
X = Vo t + ½ to t²
Time is what it takes traffic light to turn red is t = 2.0 s
X = 13.33 2 + 1.2 (-7) 2²
X = 12.66 m
It stops car before reaching the traffic light turning to red
Let's analyze what happens if you accelerate, let's calculate the acceleration of the vehicle
V2 = Vo + a t2
a = (V2-Vo) / t2
a = (19.44-13.33) /6.6
a = 0.926 m / s2
This is the acceleration to try to pass the interception, now let's calculate the distance it travels in the time the traffic light changes from yellow to red (t = 2.0 s)
X = Vo t + ½ to t²
X = 13.33 2 + ½ 0.926 2²
X = 28.58 m
Since the vehicle was 30 m away, the interception does not happen
