Answer: 0.016 h
Explanation:

It is given that, biker has an average speed = 18 km/h
Total distance traveled = 0.30 km
Therefore, time taken by biker to travel this distance:

Thus, the biker takes 0.016 hours to travel the segment of 0.30 km at an average speed of 18 km/h.
Answer:
Given that the block have two applied masses 250 g at East and 100 g at South. In order to make a situation in which block moves towards point A, we have to apply minimum number of masses to the blocks. In order to prevent block moving toward East, we have to apply a mass at West, equal to the magnitude of mass at East but opposite in direction. Therefore, mass of 250 g at West is the required additional mass that has to be added. There is already 100 g of mass acting at South, that will attract block towards South or point A. No need to add further mass in North-South direction.
Answer:
v=8m/s
Explanation:
To solve this problem we have to take into account, that the work done by the friction force, after the collision must equal the kinetic energy of both two cars just after the collision. Hence we have
![W_{f}=E_{k}\\W_{f}=\mu N=\mu(m_1+m_1)g\\E_{k}=\frac{1}{2}[m_1+m_2]v^2](https://tex.z-dn.net/?f=W_%7Bf%7D%3DE_%7Bk%7D%5C%5CW_%7Bf%7D%3D%5Cmu%20N%3D%5Cmu%28m_1%2Bm_1%29g%5C%5CE_%7Bk%7D%3D%5Cfrac%7B1%7D%7B2%7D%5Bm_1%2Bm_2%5Dv%5E2)
where
mu: coefficient of kinetic friction
g: gravitational acceleration
We can calculate the speed of the cars after the collision by using

Now , we can compute the speed of the second car by taking into account the conservation of the momentum

the car did not exceed the speed limit
Hope this helps!!
We are going to rewrite each number:
(4.48E-8) = 0.0000000448
(5.2E-4) = 0.00052
We observe that when multiplying, the exponent will be on the order of 10 ^ -11
Doing the multiplication we have:
(4.48E-8) * (5.2E-4) = 2.3296E-11
Rewriting:
(4.48E-8) * (5.2E-4) = 2.33E-11
Answer:
2.33E-11