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.
Answer:
a. 240 N due east
b. 540 N due west
Explanation:
Let east be the reference direction
(a) if the resultant force has a magnitude of 390 N and points east, and the 1st force is 150N due East, then the additional force would also due east and has a magnitude of
390 - 150 = 240 N
(b) if the resultant force has a magnitude of 390 N and points west, it would be -390N is eastern reference, and the 1st force is 150N due East, then the additional force would also due east and has a magnitude of
-390 - 150 = -540 N
This force would point west
Answer:
0.25
Explanation:
Friction force is the normal force times the coefficient of friction.
F = Nμ
50 N = (200 N) μ
μ = 0.25
Answer:
the person will be in the shore at 10.73 minutes after launch the shoe.
Explanation:
For this we will use the law of the lineal momentum.

Also,
L = MV
where M is de mass and V the velocity.
replacing,

wher Mi y Vi are the initial mass and velocity, Mfp y Vfp are the final mass and velocity of the person and Mfz y Vfz are the final mass and velocity of the shoe.
so, we will take the direction where be launched the shoe as negative. then:
(70)(0) = (70-0.175)(
) + (0.175)(-3.2m/s)
solving for
,
= 
= 0.008m/s
for know when the person will be in the shore we will use the rule of three as:
1 second -------------- 0.008m
t seconds-------------- 5.15m
solving for t,
t = 5.15m/0.008m
t = 643.75 seconds = 10.73 minutes
Internal energy<span> is defined as the </span>energy<span> associated with the random, disordered motion of molecules. It is denoted by U and calculated by the expression:
</span>Δ<span>U = Q - W
We calculate as follows:
</span>ΔU = 68 J - 32 J
ΔU = 36 J