Answer:
vB = 8.57[m/s]
Explanation:
Since there is no external force that generates momentum, the amount of momentum is conserved so you will have the following equation
![m_{A}*v_{A}=m_{B}*v_{B}\\Where:\\m_{A}= 90[kg]\\v_{A}=10[m/s]\\m_{B}=105[kg]\\\\Therefore:\\\\v_{B}=\frac{m_{A}*v_{A}}{m_{B}}\\ v_{B}=\frac{90*10}{105}\\v_{B}=8.57[m/s]](https://tex.z-dn.net/?f=m_%7BA%7D%2Av_%7BA%7D%3Dm_%7BB%7D%2Av_%7BB%7D%5C%5CWhere%3A%5C%5Cm_%7BA%7D%3D%2090%5Bkg%5D%5C%5Cv_%7BA%7D%3D10%5Bm%2Fs%5D%5C%5Cm_%7BB%7D%3D105%5Bkg%5D%5C%5C%5C%5CTherefore%3A%5C%5C%5C%5Cv_%7BB%7D%3D%5Cfrac%7Bm_%7BA%7D%2Av_%7BA%7D%7D%7Bm_%7BB%7D%7D%5C%5C%20v_%7BB%7D%3D%5Cfrac%7B90%2A10%7D%7B105%7D%5C%5Cv_%7BB%7D%3D8.57%5Bm%2Fs%5D)
Answer:
False
Explanation:
Physical features of earth's surface like mountains, deserts and oceans are not the barriers in today's modern world. Technological improvements in the transportation and communication has removed these barriers. So they are not barriers anymore.
Potential energy = (weight) x (height)
After the car has been raised 2.5 meters, it has
(11,000) x (2.5) = 27,500 Joules
MORE potential energy than it had before it was lifted.
That's the energy that has to come from the work you do to lift it.
Since no mechanical process is ever 100% efficient, the work required
to accomplish this task is <em>at least 27,500 joules</em>.
