In 2008 a tornado swept across the northern part of Lake City, Florida, damaging about 50 homes and a dozen business establishme
nts. What would people in Lake City, Florida, most likely do if a tornado alert is sounded? Select one:
a. They would rush to high lands.
b. They would install heaters in their houses.
c. They would find a safe room within a building.
d. They would buy a tornado detecting instrument.
The correct option is C. According to the safety tips that is usually released by the government, it is typically advised that during a tornado, that people should go to the interior room on the lowest base of their houses, the room should be windowless. When in this room, it is advisable that one should get under a furniture that can not be easily damage and then use one's arms to protect the head and the neck.
If a pulley system has an efficiency of 74.2%, then only that fraction of the work performed will be useful. 74.2%=0.742. 0.742*200 is about 148J. Hope this helps!
Applying the work-energy theorem, if we can neglect the friction between truck and road, the total change in kinetic energy must be equal to the work done by the external forces.
This work, is just 4,475 J.
So we can write the following equation:
where m= mass of the truck = 2.5*10³ kg.
So, we can find the speed v, as follows:
b)
The work done by the man, is just the horizontal force applied, times the displacement produced by the force horizontally:
