Answer:
W = 650 [kJ]
Explanation:
The definition of work is denoted by the product of force by the distance traveled by the body, this distance traveled corresponds to the direction of the force.
In this case we have:
d = distance = 2.6[km] = 2600 [m]
F = force = 250 [N]
W = F*d = 250 * 2600 = 650000 [J] or 650 [kJ]
Answer:
4°C
Explanation:
Water is densest at 4°C. Since dense water sinks, the bottom of the lake will be 4°C.
Answer:
Surely Achilles will catch the Tortoise, in 400 seconds
Explanation:
The problem itself reduces the interval of time many times, almost reaching zero. However, if we assume the interval constant, then it is clear that in two hours Achilles already has surpassed the Tortoise (20 miles while the Tortoise only 3).
To calculate the time, we use kinematic expression for constant speed:
The moment that Achilles catch the tortoise is found by setting the same final position for both (and same time as well, since both start at the same time):