Answer:
I think u are traeling at speed of light and not ur friend
Explanation:
If an icy surface means no friction, then Newton's second law tells us the net forces on either block are
• <em>m</em> = 1 kg:
∑ <em>F</em> (parallel) = <em>mg</em> sin(45°) - <em>T</em> = <em>ma</em> … … … [1]
∑ <em>F</em> (perpendicular) = <em>n</em> - <em>mg</em> cos(45°) = 0
Notice that we're taking down-the-slope to be positive direction parallel to the surface.
• <em>m</em> = 0.4 kg:
∑ <em>F</em> (vertical) = <em>T</em> - <em>mg</em> = <em>ma</em> … … … [2]
<em />
Adding equations [1] and [2] eliminates <em>T</em>, so that
((1 kg) <em>g</em> sin(45°) - <em>T </em>) + (<em>T</em> - (0.4 kg) <em>g</em>) = (1 kg + 0.4 kg) <em>a</em>
(1 kg) <em>g</em> sin(45°) - (0.4 kg) <em>g</em> = (1.4 kg) <em>a</em>
==> <em>a</em> ≈ 2.15 m/s²
The fact that <em>a</em> is positive indicates that the 1-kg block is moving down the slope. We already found the acceleration is <em>a</em> ≈ 2.15 m/s², which means the net force on the block would be ∑ <em>F</em> = <em>ma</em> ≈ (1 kg) (2.15 m/s²) = 2.15 N directed down the slope.
Answer:
momentum=mass×velocity
momentum =400kg×20m/s=8000kg.m/s
Answer:
Explanation:
Heat required to warm the water from 20 degree to 51 degree
= mct
= 131 x 4150 x ( 51 - 20 )
= 16853150 J
Power of heating element
= v² /R
Heat generated in 31 min
= (v² / r ) x 31 x 60 = 16853150
r = (240 x 240 x 31 x 60) / 16853150
6.35 ohm
In this case heat required will change so time will also change
Heat required =
131 x 4150 x ( 100-51 )
= 26638850 J
If time required be t hour
Energy consumed
Power x time
= (v² / r ) x t x 60 = 26638850
t = 26638850 x 6.35 / (240 x 240 x 60 )
= 48.95 h
Heat required to evaporate water at 100 degree
= mass x latent heat
= 131 x 2260000
= 296060000 J
Total heat required
= 296060000 + 26638850 + 16853150
= 339552000 J
time required = 339552000 x 6.35 / (240 x 240 x 60 )
= 623.88 h .
<span>The answer would be, C. The reactions go to completion</span>