For this problem the figure below shows the representation of a student who pulls on a 20kg box. We know this variables:
Weight of the box = 20kg
Force used by the student to pull on the box = 50N (This is the tension T)
Angle relative to the horizontal = 45 degrees
Aceleration of the box =
The figure also shows the Free-Body diagram, Applying Newton's Second Law we can find the equation for this diagram, related to the x-axis as:
Isolating
:
<span>That is the friction force on the box.</span>
Answer:
A. Heat flows from an object at higher temperature to an object at lower temperature
Explanation:
The option A obeys the 2nd law of thermodynamics. The heat will flow from the object at higher temperature to the object at Lower temperature till they reach an equilibrial state.
Heat doesn’t necessarily flow from an object with higher thermal energy to an object with lower thermal energy because an object has a higher thermal energy when it’s mass is more than the other. This makes B wrong.
C is wrong because heat moves from an object with higher temperature to objects with Lower temperature regardless of the state of matter.
Knowing the force and distance allows you to calculate the work done.
Then, if you know the TIME, you can calculate the power.
Answer:
a.
b. decrease
c. 43.5psi
Explanation:
Answer:
a.
Explanation:
from the questions, the car has four tires which support the weight equally.we can conclude that the weight support by each tire is
weight support of each tire =1420/4=355kg.
a. since
we need to determine the force,
the "g" is the acceleration due to gravity which has a constant value of
hence the force on each tire is
Also, since the pressure is giving in psi, we have to convert it to pascal
since 1psi=6895pascal
hence 35psi to pascal is
.
From the expression for pressure
we have
to cm we multiply by
b. The effect of the pressure can be determine from the relationship between the pressure and the area using the pressure formula
hence an increase in the pressure will lead to a decrease in the contact Area
C. if the area ia now converting to meter square
the pressure now is
converting to psi we have