Think about the process of pulling down the spring and letting it go. For this event, list each form of energy associated with t
1 answer:
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Answer: The angle between the wire segment and the magnetic field 66.42°
Explanation:
Please see the attachment below
We simply use the formula,
Given, velocity = 4 m per s and distance = 120 m.
Substituting these values, we get
.
Thus, required time for the elevator in order to travel 120 m upwards is 30 s.
Answer:
Explanation:
The only thing I can figure you need here is the accleration of the sled. The equation we need to find this is Newton's Second Law that says that sum of the forces acting on an object is equal to the object's mass times its acceleration. For us, that looks like this because of the friction working against the sled:
F - f = ma but of course it's much more involved than that simple equation! We have the F value as 230 N, and we have the mass as 105, but we do not have the frictional force, f, and we need it to solve for a in the above equation. We know that
f = μ where μ is the coefficient of friction, and
is the normal force, aka weight of the object. We will use the coefficient of friction and find the weight in order to fill in for f:
so
so the weight of the sled is
1.0 × 10³ with the correct number of sig dig there. Now to find f:
f = (.025)(1.0 × 10³) so
f = 25 to the correct number of sig fig. Now on to our "real" equation:
F - f = ma and
230 - 25 = 105a. We have to do the subtraction first, round, and then divide since the rules for addition and subtraction are different from the rules for dividing and multiplying.
230 - 25 will round to the tens place giving us 210. Then
210 = 105a. 210 has 2 sig figs in it while 105 has 3, so we will divide and round to 2 sig fig:
a = 2.0 m/sec²
Answer:
a) is the height where the rocket stops accelerating and its fuel is finished and starts decelerating while it still continues to move in the upward direction.
b) is speed of the rocket going when it stops accelerating.
c)
d)
e) Zero, since the average velocity is the net displacement per unit time and when the rocket strikes back the earth surface the net displacement is zero.
Explanation:
Given:
acceleration of rocket,
time for which the rocket accelerates,
<u>For the course of upward acceleration:</u>
using eq. of motion,
where:
initial velocity of the rocket at the launch
height the rocket travels just before its fuel finishes off
so,
a) is the height where the rocket stops accelerating and its fuel is finished and starts decelerating while it still continues to move in the upward direction.
<u>Now the velocity of the rocket just after the fuel is finished:</u>
b) is speed of the rocket going when it stops accelerating.
After the fuel is finished the rocket starts to decelerates. So, we find the height of the rocket before it begins to fall back towards the earth.
Now the additional height the rocket ascends before it begins to fall back on the earth after the fuel is consumed completely, at this point its instantaneous velocity is zero:
using equation of motion,
where:
acceleration due to gravity
final velocity of the rocket at the top height
c) So the total height at which the rocket gets:
d)
Time taken by the rocket to reach the top height after the fuel is over:
Now the time taken to fall from the total height:
Hence the total time taken by the rocket to strike back on the earth:
e)
Zero, since the average velocity is the net displacement per unit time and when the rocket strikes back the earth surface the net displacement is zero.