Answer:
Only the 4 th statement is true that is bed 1 and 3 are older than 4.
Explanation:
The 5 beds are numbered from 1 to 5 , 1 being the lowest and 5 being the topmost bed.
We are given 4 statements and we have to find out which all are true.
(<u>a)Bed 4 is older than bed 2 </u>
This is wrong because the lower beds are older than beds that are higher.
<u>(b)Bed 3 is older than beds 2 and 4</u>
This is also wrong because the 2 is older than 3
(<u>c)Bed 5 is the oldest </u>
This is wrong because bed 1 is the oldest
(<u>d)Beds 1 and 3 are older than 4</u>
This is true as lower beds are older
<u />
Answer:
Using the new cylinder the heat rate between the reservoirs would be 50 W
Explanation:
- Conduction could be described by the Law of Fourierin the form:
where
is the rate of heat transferred by conduction,
is the thermal conductivity of the material,
and
are the temperatures of each heat deposit,
is the cross area to the flow of heat, and
is the distance that the flow of heat has to go. - For the original cylinder the Fourier's law would be:
, and if
, then the expression would be:
where
is the diameter of the original cylinder, and
is the length of the original cylinder. - For the new cylinder, in the same fashion that for the first, Fourier's Law would be:
,where
is the heat rate in the second case,
and
are the new diameter and length. - But,
and
, substituting in the expression for
:
. - Rearranging:
. - In the last declaration of
, it could be noted that the expressión inside the parenthesis is actually
, then:
. - <u>It should be noted, that the temperatures in the hot and cold reservoirs never change.</u>
Answer:
1.10 m/s
Explanation:
Linear speed is given by
Kinetic energy is given by
Potential energy
PE= mgh
From the law of conservation of energy, KE=PE hence
where m is mass, I is moment of inertia,
is angular velocity, g is acceleration due to gravity and h is height
Substituting m2-m1 for m and 0.5l for h,
for
we obtain
and making v the subject
For the rod, moment of inertia
and for sphere
hence substituting 0.5L for R then
For the sphere on the left hand side, moment of inertia I
while for the sphere on right hand side,
The total moment of inertia is therefore given by adding
Substituting
for I in the equation
Then we obtain
This is the expression of linear speed. Substituting values given we get
Answer:
291.598 N-m
291.6 N-m
Explanation:
Let's first take a look at the free bodily diagrammatic representation.
The first diagram will aid us in answering question (a), so as the second diagram will facilitate effective understanding when solving for question (b).
Let's first determine our angle θ from the diagram
To find angle θ ; we have :
tan θ = 
tan θ = 
tan θ = 1.333
θ = tan⁻¹ (1.333)
θ = 53.13°
Now, to determine the moment about B of the force exerted by the cord at point A by resolving that force into horizontal and vertical components applied at point A.
We have:

where Force(F) = Force in the cord AC = 1350 N and θ = 53.13° ; we have:




Since the negative sign illustrates just the clockwise movement ; then the moment about B of the force exerted by the cord at point A by resolving that force into horizontal and vertical components applied at point A = 291.598 N-m
b) From the second diagram, taking the moment at point B
,
we have:



where Force(F) = 1350 N and θ = 53.13° ; we have:



Since the negative sign illustrates just the clockwise movement ; then the moment about B of the force exerted by the cord at point A by resolving that force into horizontal and vertical components applied at point C = 291.6 N-m