Explanation:
Q= mc∆T
∆T= 5-24=- 19
Q= 0.5*4186*-19
Q= -39767 J
negative sign show heat releases
Postitive ions have more protons than electrons, because protons are positively charged. Electrons have a negative charge, so if there were less protons than electrons the job would be negative. If there were the same amount of both, then the positive and negative charges balance each other out, making a neutral charge.
Answer:
96%
Explanation:
To find the values of the motor efficiency you use the following formula:

P_o: output power = 864J/0.5min=864J/30s=28.8W
P_i: input power = I*V = (3A)(12V) = 36W
By replacing this values you obtain:

hence, the motor efficiency is about 96%
traslation:
Pentru a găsi valorile eficienței motorului, utilizați următoarea formulă:
P_o: putere de ieșire = 864J / 0.5min = 864J / 30s = 28.8W
P_i: putere de intrare = I * V = (3A) (12V) = 36W
Înlocuind aceste valori obțineți:
prin urmare, eficiența motorului este de aproximativ 96%
Explanation:
Given:
v₀ = 0 m/s
v = 49 m/s
a = 9.8 m/s²
Find: t
v = at + v₀
49 m/s = (9.8 m/s²) t + 0 m/s
t = 5 s