Answer:
<em>The first option best compares both ramps: "It takes less effort to wheel boxes up the 5 m ramp, but the distance is greater"</em>
Explanation:
Power and Work
If an object is being lifted by a vertical distance y, the work done by the agent is the same regardless of the path taken to reach that heigh. But the power could be different since it depends on the time needed to do the work.
The question talks about 'effort' which we'll assume to be the power, since, as noted above, the work is the same by using any of the ramps. The 5 m ramp makes the job easier because the worker has to push less. It's due to the fact that the component of the weight depends on the sine of the angle formed by the ramp with the floor. The larger ramp makes a shorter angle, thus requiring less effort, through a longer distance.
Thus, the first option best compares both ramps:
<em>It takes less effort to wheel boxes up the 5 m ramp, but the distance is greater</em>
Answer: Symbol A
Explanation:
The four symbols described here represent:
- Symbol A shows two dots and a line draw from one not connected to the other. --> this is an open switch. A switch is component of a circuit that is used to open/close the circuit in order to interrupt/allow the flow of current through the circuit. In this case, the switch is open, since the line does not connect the second dot.
- Symbol B shows two dots and a line draw from one connected to the other. --> this is the symbol used to represent the switch when it is closed, so it is a closed switch.
- Symbol C shows vertical lines in the pattern long, short, long, and short with a plus and minus symbol on it. --> this symbol represents a battery, which consists of two or more cells and provides the electromotive force that pushes the electrons along the circuit.
Therefore, the correct symbol representing the open switch is
Symbol A
Here, F = m * a
F = m * v/t
Here, m = 81 Kg
v = 22 m/s
t = 1,4 s
Substitute their values,
F = 81 * 22/1.4
F = 81 * 15.71
F = 1273 N
So, Closest value from your options is 1300 N
In short, Your Answer would be Option B
Hope this helps!