Answer: A) because forces are what stop and start motion
Explanation:
From Newton's first law, an object tends to stay in state of rest or motion unless acted upon by an unbalanced external force. This is also known law of inertia. This is because a force can stop or start a motion. A force cause body to accelerate to decelerate otherwise the body continues with constant speed.
This question is a critical question. as we all know, when energy is added to any state of water, the particles move faster. and when energy is taken away from any state of water, the particles reduce speed. same with the particles of air. when energy is added; they move faster. when energy is removed; they move slower. so the answer is they move faster
the anwser is c is always the best anwser
<span>Recall formula for Kinetic energy is:
KE = 1/2mv^2, where KE = 275J
and momentum (which is 25.0 kg m/s) = m*v
Therefore substitute for KE and mv in the equation above to get speed
=> 275 = 0.5 * 25 * v
v = 275/12.5
v = 22m/s
to get mass m, recall momentum = m*v
=> 25= 22*m
m= 25/22 = 1.3663kg</span>
Answer:
Final velocity = 7.677 m/s
KE before crash = 202300 J
KE after crash = 182,702.62 J
Explanation:
We are given;
m1 = 1400 kg
m2 = 4700 kg
u1 = 17 m/s
u2 = 0 m/s
Using formula for inelastic collision, we have;
m1•u1 + m2•u2 = (m1 + m2)v
Where v is final velocity after collision.
Plugging in the relevant values;
(1400 × 17) + (4700 × 0) = (1400 + 1700)v
23800 = 3100v
v = 23800/3100
v = 7.677 m/s
Kinetic energy before crash = ½ × 1400 × 17² = 202300 J
Kinetic energy after crash = ½(1400 + 1700) × 7.677² = 182,702.62 J
