"A machine can decrease either the input force or the input distance needed to do a given amount of work" is the best statement that describes why a machine is useful.
Answer: Option D
<u>Explanation
:</u>
A machine is simply defined as a device that helps humans, helping them to transfer the required amount of force to compete any task, changing the direction of motion, increasing the magnitude of force to complete any task, reduce the time or distance needed to cover while performing any task.
Machines can be simple mechanical device or a combination of multiple mechanical or technical devices to reduce the amount of input force or increase the output.
I’d probably say a forest or a dessert
Answer:
36365.4 Joules
Explanation:
The quantity of Heat Energy (Q) released on cooling a heated substance depends on its Mass (M), specific heat capacity (C), and change in temperature (Φ)
Thus, Q = MCΦ
Since, M = 45.4 g
C = 3.56 J/g°C,
Φ = 250°C - 25°C = 225°C
Q = 45.4g x 3.56J/g°C x 225°C
Q= 36365.4 Joules
Thus, 36365.4 Joules of heat energy is released when the lithium is cooled.
D)plastic copper
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