Answer:
B
Explanation:
<em>A. His speed is 0 m/s
</em>
<em>B. His velocity is 12 m/s
</em>
<em>C. His velocity is 0 m/s
</em>
<em>D. His acceleration is 12 m/s</em>
Total distance traveled by John = 120 + 120 = 240 meters
Total time taken by John to cover the distance = 10 + 10 = 20 s
<em>Average speed of John = total distance traveled/total time taken</em>
= 240/20 = 12 m/s
Hence, the average speed/velocity of John throughout the journey is 12 m/s.
The correct option is B.
Sound moves faster in warmer temperature because the particles move faster
Answer:
289.1kg
Explanation:
because W=M*G, and M=W/G, so 2891N/10m/s²=289.1kg
Answer:
-2.85 * 10^(-17) J
Explanation:
Parameters given:
Final velocity, v = 9 * 10^6 m/s
Initial velocity, u = 4.5 * 10^6 m/s
Using the conservation of energy formula, total energy is conserved:
K.Ein + PEin = KEf + PEf
K.Ef - K.Ein = P.Ein - P.Ef
=> -∆P.E = K.Ef - K.Ein
∆P.E = K.Ein - K.Ef
∆P.E = ½mu² - ½mv²
∆P.E = ½m[(4.5 * 10^6)² - (9 * 10^6)²]
∆P.E = ½ * 9.31 * 10^(-31) * (-61.25 * 10¹²)
∆P.E = -2.85 * 10^(-17) J
Answer:
D. A 10 kg rock at 15°C
Explanation:
Thermal energy is heat energy, meaning that the hotter rocks will have more energy.
The heavier/larger rocks can store more energy.
So if we combine the largest two variables, we get a 10kg rock at 15°C.
