The kinetic energy (KE) of a 0.155 kg arrow that is shot from ground level, upward at 31.4 m/s, when it is 30.0 m above the ground is 30.85 J
Assuming air friction is negligible,
a = - 9.8 m / s²
u = 31.4 m / s
s = 30 m
v² = u² + 2 a s
v² = 31.4² + ( 2 * - 9.8 * 30 )
v² = 985.96 - 588
v² = 397.96 m / s
KE = 1 / 2 m v²
KE = 1 / 2 * 0.155 * 397.96
KE = 0.0775 * 397.96
KE = 30.85 J
Therefore, the kinetic energy ( KE ) when it is 30.0 m above the ground is 30.85 J
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Answer:
The speed with which the pebble strikes the ground is 30.4m/s
Explanation:
Initial velocity (u) = 17.5m/s, height (h) = 31.5m, acceleration due to gravity (g) = 9.8m/s^2
V^2 = u^2 + 2gh = 17.5^2 + 2×9.8×31.5 = 306.25 + 617.4 = 923.65
V^2 = 923.65
V = √923.65 = 30.4m/s
Answer:
In order to hit the same point with the second ball, you should throw it at an angle of 18° above the horizontal.
Explanation:
Horizontal reach formula for projectiles tells us
where 
is the initial velocity and 
the angle above the horizontal.
Since for both shots the reach must be the same, we have
.
45 kg * 9.8 m/s^2 = <u>441 N.</u>
Hello!
The <span>biochemical process that liberates energy content of food for living organs is called catabolism.
Catabolism is a process in which big molecules like those in the food we eat are broken down into small ones that can be used by the living organism to obtain energy. The energy that is liberated in this process is stored in molecules of adenosine triphosphate (ATP). These molecules are used by cells to produce energy in the process called cellular respiration, catalyzed by the enzyme ATPase.
Have a nice day!
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