According to the law of conservation of energy,
A. an object loses most of its energy as friction
<u>B. the total amount of energy for a system stays the same</u>
Energy is never lost due to the law of conservation
C. the potential energy of an object is always greater than its kinetic energy
D. the kinetic energy of an object is always greater than its potential energy
Answer:
a) 0.25m
b) 5 m/s
Explanation:
When the spring is compressed both boxes are moving with the same velocity, so applying the principle of linear momentum conservation:
Now applying the principle of energy conservation:
We got that the maximum compression is 0.25m.
Answer:
=1419.19 meters.
Explanation:
The time it takes for the shell to drop to the tanker from the height, H =1/2gt²
610m=1/2×9.8×t²
t²=(610m×2)/9.8m/s²
t²=124.49s²
t=11.16 s
Therefore, it takes 11.16 seconds for a free fall from a height of 610m
Range= Initial velocity×time taken to hit the tanker.
R=v₁t
Lets change 300 mph to kph.
=300×1.60934 =482.802 kph
Relative velocity=482.802 kph-25 kph
=457.802 kph
Lets change 11.16 seconds to hours.
=11.16/(3600)
=0.0031 hours.
R=v₁t
=457.802 kph × 0.0031 hours.
=1.41918 km
=1.41919 km × 1000m/km
=1419.19 meters.
C = 200 j/g*C
m = 2g
ΔT = 55 - 35 = 20C
Heat = mcΔT = 2 * 200 * 20 = 8000J = 8kJ
Answer:
0.79
Explanation:
Using Snell's law, we have that:
n(1) * sin θ1 = n(2) * sinθ2
Where n(1) = refractive index of air = 1.0003
θ1 = angle of incidence
n(2) = refractive index of second substance
θ2 = angle of refraction
The angle of reflection through the unknown substance is the same as the angle of incidence of air. This means that θ1 = 32°
=> 1.0003 * sin32 = n(2) * sin42
n(2) = (1.0003 * sin32) / sin42
n(2) = 0.79
