Answer:
Explanation:
Given
distance traveled by Passenger train is 
distance traveled by Freight train is 
Both take same time to travel
suppose speed of freight train is x mph
so speed of passenger train is 20+x mph
we know time
speed of passenger train 
Answer:
c. is negative
Explanation:
When the magnitude of force is multiplied with the force vector's projection along the direction of the vector of displacement which is negative as it is a resistive force we get the work done.
As the wind is acting in opposite direction of the force which is being applied by the plane the work done will be negative. Also, the net work will be the sum of many smaller negative quantities.
Hence, the answer here is negative.
As more resistors are added in parallel across a constant voltage source, there are more paths for current to take. So more current dribbles out of the source, and the total current supplied by the source increases.
The power supplied by the battery is (voltage) x (current). So if the voltage is constant and the current increases, the power being supplied must also increase.
<em>choice-c</em>
