Answer:
A
Explanation:
All of the frictions are the same, but weight always goes straight down so it can only be A or B. Since they are going down a slope, then the normal force must be sloped. A is the only one out of A and B with a sloped normal force, so it has to be A
<span>1. Get a graduated cylinder.
2. Fill the graduated cylinder to a known amount of water. Record the amount of water in the cylinder.
3. Place rock into the graduated cylinder
4. Measure the new volume of the graduated cylinder with the rock in it.
5. Take the difference of the new volume and the old volume and that is the volume of the rock.</span>
The law of conservation of momentum tells us that momentum
is conserved, therefore total initial momentum should be equal to total final
momentum. In this case, we can expressed this mathematically as:
mA vA + mB vB = m v
where, m is the mass in kg, v is the velocity in m/s
since m is the total mass, m = mA + mB, we can write the
equation as:
mA vA + mB vB = (mA + mB) v
furthermore, car B was at a stop signal therefore vB = 0,
hence
mA vA + 0 = (mA + mB) v
1800 (vA) = (1800 + 1500) (7.1 m/s)
<span>vA = 13.02 m/s</span>