Answer:
The normal force the ground exerts on the block, F = -300 N
Explanation:
Given data,
The block pulled up with a tension force, T = 100 N
The weight of the block, W = 300 N
The weight of the block is due to the force of attraction of gravitation.
The surface exerts a force that is equal and opposite to the force acting on the block due to gravitation.
The weight of the block,
W = mg
300 N
The normal force the ground exerts on the block,
F = - mg
= - 300 N
Hence, the normal force the ground exerts on the block, F = -300 N
At 100 km/hr, the car's kinetic energy is
KE = (1/2) (mass) (speed)²
KE = (1/2) (1575 kg) ( [100 km/hr] x [1000 m/km] x [1 hr/3600 sec] )²
KE = (787.5 kg) (27.78 m/s)²
KE = 607,639 Joules
In order to deliver this energy in 2.9 seconds, the engine must supply
(607,639 J / 2.9 sec) = 209,531 watts
<em>Power = 281 HP</em>
a. work is the time it takes to move an object once acted upon by a force