Answer:
The speed is
and the direction is heading north.
Explanation:
In collisions the force exerted by the objects that collide is higher enough than the external forces that we can neglect that external forces, with that assumption we can use the conservation fo momentum law that states, final total momentum (pf) is equal initial total momentum (pi) if there’re not external forces or they are small enough to be neglected. Mathematically:

The total momentum is the sum of the momentum of each of the bodies we're dealing, in our case the moment of each car, then:

with pn the momentum of the 1000kg car heading north and ps the 800kg car heading south. Momentum is defined as mass times velocity, then:
(1)
It's important to note that when we talk about momentum and velocity direction matters, so we're are going to choose a system of reference where quantities pointing north are positive and pointing south are negative. So, the initial velocity of 1000 kg car is vni=5 m/s, initial velocity of 800 kg car is vsi=-4 m/s and the final velocity of 1000 kg car is vnf=-1 m/s. Now we can solve (1) for vsf and use the values we already have:

Because the sign is positive the direction is to heading north.
Answer:
4*10^-2
Explanation:
for the scientific notation the first number must be between 1 and 10, so in this case it is 4. 4/100 is also equal to 0.04, and if we could the number of places before 4, there are two, therefore 4 times 10 to the power of -2
A contact force since you are making physical contact with the dog
Mark my brainliest please
It depends on mass and distance.
Answer:
F = 176.175 N
Explanation:
given,
radius of merry - go - round = 2.7 m
mass of the disk = 800 kg
speed of the merry- go-round = 18 rpm
= 18 
= 1.88 rad/s
time = 13 s
mass of two children = 25 kg
ω = ω₀ + α t
1.88 = 0 + α(13)
α = 0.145 rad/s²
we know
τ = I α
so,
τ = I α
τ = 3280.5 x 0.145
τ = 475.67 N m
τ = F x r
475.67 = F x 2.7
F = 176.175 N