Answer:
<u>2. - B. </u>
<u>3. - True. </u>
<u>4. - B. </u>
<u>5. - D. </u>
Explanation:
2. To find the speed in feet per minute, you need to divide the time by time and divide the feet by the time
2/2 = 1 minute
100/2 = 50 feet
3. 45 N - 20 N = 15 N
So the difference between the forces is 15 N
4. As just about everyone knows, when something falls, that is because of gravity. Gravity is the force that pulls everything.
5. Inertia is when an object stays unchanged. So if something stays in motion or does not stop, it has not changed
There’s 10mm in a cm: 22mm
Answer:
Explanation:
The force of friction acting on the system
= .04 x 9.8 ( 10.2 + 7 )
= 6.74 N
Net force = 8.9 - 6.74
= 2.16 N
Acceleration in the system
= 2.16 / ( 10.2 + 7 )
= .12558 m / s ²
Contact force between boxes = FP
Considering force on box A
Net force = 8.9 - FP
Applying Newton's law on box A
8.9 - FP = 10.2 x .12558
= 1.28
FP = 8.9 - 1.28
= 7.62 N
The process of heat exchange is involved in the operation of all heat engines.
<u>Explanation:</u>
A heat engine refers as the system which converts thermal or heat and chemical energy into mechanical energy. Then, these can be utilised for mechanical work. This is done by raising the active substances from higher to lower temperature state. In simple words, it produces macroscopic movement from the heat.
For example, when people rub their hands, friction converts mechanical energy (the movement of our hands) into thermal energy (hands warm up). Heat engines work exactly the opposite; they take energy to warm up (in relation to the environment) and release it for movement. This movement is often transformed into electricity by a generator. It shows that there is exchange of heat involved in all of its processes.
Answer:
Explanation:
Given
Two springs with spring constant 
and 
(a)If they are stretched using the same force
Force 
where 
and 
are the extension in the spring
so 
therefore 
Work done is given by
thus 
(b)If they are stretched the same distance
Thus 
For same extension, work done by Force 1 is more
