Answer:
63.9 m/s
Explanation:
Parameters given:
Mass of small car, m = 1200 kg
Mass of SUV, M = 4000 kg
Speed of SUV, V = 35 m/s
Their kinetic energy of the small car is equal to the kinetic energy of the SUV, hence:
0.5 * m * v² = 0.5 * M * V²
=> 0.5 * 1200 * v² = 0.5 * 4000 * 35²
600 * v² = 2450000
v² = 2450000/600
v² = 4083.3
=> v = 63.9 m/s
The speed of the small car is 63.9 m/s.
Answer:
16 m/s
Explanation:
Given that
y momentum = 0.080 *25 = 2
x momentum = 0.075*20 = 1.5
total momentum = √(4 + 2.25)
Total momentum = √6.25
Total momentum = 2.5
total mass = mass of x and y momentum = 0.075 + 0.080 = 0.155
speed of mass center = total momentum / total mass = 2.5/0.155 = 16.
And thus, the speed of the center of mass of this two-particle system at this instant is 16 m/s
The momentum, p, of any object having mass m and the velocity v is

Let
and
be the masses of the large truck and the car respectively, and
and V_S be the velocities of the large truck and the car respectively.
So, by using equation (i),
the momentum of the large truck 
and the momentum of the small car
.
If the large truck has the same momentum as a small car, then the condition is

The equation (ii) can be rearranged as

So, the first scenario:


So, to have the same momentum, the ratio of mass of truck to the mass of the car must be equal to the ratio of velocity of the car to the velocity of the truck.
The other scenario:


So, to have the same momentum, the ratio of mass of truck to the velocity of the car must be equal to the ratio of mass of the car to the velocity of the truck.
the answer would be b. it`s half as great