The normal reaction between the television and the table is
N = 12 × 9.8 m/s² = 117.6 Newtons
But the static coefficient of friction is μ = 0.83
When the television is about to slide on the table, the applied force should overcome the force due to static friction;
Thus; the applied force should be at least
F = μN
= 0.83 × 117.6 N
= 97.608 Newtons
Therefore; the minimum applied force will be 97.6 Newtons.
Mass=600kg
Velocity =15m/s
Momentum(p)=?
Now,
P=mass x velocity
=600x15
=9000kgm/s
The correct answer is 10 years
Answer:
Before giving an injection, a nurse dabs some alcohol onto the patient`s arm. This makes the patient`s skin feels cold. Explain Why ?
<em> Evaporative cooling makes this to be possible</em>
Explanation:
The concept
For a liquid to evaporate, there must be a breakdown of the bond between the molecules of the liquid. These bonds are broken when the molecules gain heat energy. So basically evaporation occurs when the molecules of the substance gain energy in form of heat.
Our Scenario
Just like the way our body excretes sweat on a sunny day, alcohol takes energy from the skin to evaporate. The bond holding the molecules of alcohol breaks faster due to its low boiling point and this account why it evaporates faster. The sudden evaporation of alcohol when dabbed on the skin results in quick utilization of heat energy making the skin feel cold for some time.
The utilization of heat energy from the skin results in evaporation cooling which makes the skin feel colder.
