Answer: having to push a rough and heavy box across the floor to move it
Explanation:
The Friction force is any force that is in opposite direction of the motion of an object or fluid due to the contact of this object or fluid with other bodies.
In this sense, there are different types of friction force thath are useful in different situations:
-The <u>Static friction force</u> prevents surfaces from slipping across each other. For example, the friction between your feet and the floor keeping you from slipping.
-The <u>kinetic friction force</u> as the force that helps the tires in a moving vehicle to slow down and stop when necessary.
However, if you want to push a heavy box across the floor to move it, the friction force will not be useful at all.
Alcohol filled thermometer is used for low temperature applications. (Weather) It’s freezing point is -70 degC
While mercury freezes at -38 deg C
Mercury is/was better for human and other animal temps. High thermal coefficient of expansion mercury vs. alcohol = better resolution for small temperature changes in a medical application.
For higher temperatures alcohol will boil before mercury will.
Answer:
The deceleration is
Explanation:
From the question we are told that
The distance of the car from the crossing is 
The speed is 
The reaction time of the engineer is 
Generally the distance covered during the reaction time is

=> 
=> 
Generally distance of the car from the crossing after the engineer reacts is
=>
=> 
Generally from kinematic equation

Here v is the final velocity of the car which is 0 m/s
So

=>
42- C
43- A
44- C
45- A
46- B
47- D