Answer:
58.8J
Explanation:
Given parameters;
Mass of ball = 4kg
Height above the floor = 1.5m
g = 9.8n/kg
Unknown:
Potential energy = ?
Solution:
The potential energy of a body is the energy due to the position of the body.
It is mathematically expressed as:
Potential energy = mass x acceleration due to gravity x height
Potential energy = 4 x 9.8 x 1.5 = 58.8J
If the box is moving at constant velocity, net force must be zero, so:
F + fr = 0
fr = -F
<u>fr = -40 N</u>
Answer: Smoking cigarettes
Explanation: The other options don't cause pollution to form in the air besides smoking, from the particles it creates causing harm and damage to your lungs and fill the air with smoke particles.
The second one because you don't get shocked by plugging in something you can get electricted by putting something thin in the outlet then it will send a shock to your hand
