Answer: B
Explanation: The rocket is accelerating the the spacecraft. Accelerating relates to Newtons Second Law of Motion.
<span>1) at rest his
weight is 840 N
=> 840N = mass * g => mass = 840 N / g = 840 N / 9.8 m/s^2 = 85.7 kg
2) as the elevator rises, his weight increases to 1050 N,
The reading of the scale is the norma force of it over the body of the person.
And the equation for the force is: Net force = mass * acceleration = normal force - weight at rest
=> mass * acceleration = 1050 N - 840 N = 210 N
acceleration = 210 N / mass = 210 N / 85.7 kg = 2.45 m/s^2 (upward)
3) when the elevator slows to a stop at the 10th
floor, his weight drops to 588 N
=> mass * acceleration = 588 N - 840 N = - 252 N
=> acceleration = - 252 N / 85.71 kg = - 2.94 m / s^2 (downward)
Answer:
Acceleration at the beginning of the trip 2.45 m/s^2 upward
Acceleration at the end of the trip 2.94 m/s^2 downward
</span>
I believe the answer is A.
Since the Earth is in the Milky Way and not outside it, we cannot see the exact shape of it. Physicists have been able to track and graph the movements of the planets accurately for thousands of years, but that does not mean we know the shape of the entire solar system.<span />
The cat has two directions of motions:
The horizontal motion = Dx = 2.2 m
The vertical motion = Dy = -1.3 m (negative sign indicates that the cat is falling)
a = 9.8 m/sec^2
Vy = zero (since you are not moving up)
From the laws of motion:
<span>Dy = Vyt + 0.5ayt^2
</span>-1.3 = 0(t) + 0.5(-9.8)t^2
<span>t = 0.52s
</span>
Then, again using the laws of motion (but for the horizontal direction this time)
Dx = Vxt
<span>2.2 = Vx0.52 </span>
<span>Vx = 2.2/0.52 </span>
<span>= 4.23 m/s
</span>
<span>Therefore the cat's speed when it slid off the table is 4.23 m/s horizontally.</span>
Answer:
200N
Explanation:
mass(m) = 10 kg
acceleration(a) = 20 m/s^2
Force = mass * acceleration
= 10*20
= 200 N
Force = 200N
