Answer: Look where the points are.
Explanation:
Answer:
Explanation:
According to first law of thermodynamics:
∆U= q + w
= 10kj+(-70kJ)
-60kJ
, w = + 70 kJ
(work done on the system is positive)
q = -10kJ ( heat is given out, so negative)
∆U = -10 + (+70) = +60 kJ
Thus, the internal energy of the system decreases by 60 kJ.
<span>Final Velocity = Vf = 0 m/s --------------> (Vf = 0 because ball's speed at its max height is 0)
Initial Velocity = Vi = ?
Total time (upward & downward) = 8.0 seconds
* Time upward = 4 seconds & ................( As time for ball upward & downward is equal )
* Time downward = 4 seconds..
Gravitational Acceleration = g = -9.8 m/s²
Use Equation;
Vf = Vi - gt
0 = Vi - 9.8 * 4
0 = Vi - 39.2
39.2 = Vi
=> Vi = Initial Velocity = 39.2 m/s</span>
Waves carry energy through objects. mark me as brainlist.
