3.33 seconds.
<u>Explanation:</u>
We can find the speed of the body using the formula,
Speed = Distance traveled in meters / time taken in seconds
= 450 m / 30 seconds
= 15 m/s
So per second the distance traveled by the body is 15 m.
So time needed to travel 50 m can be found as,
time = distance/speed
= 50 m / 15 m /s
= 3.33 s
Answer:
<em>Explanation below</em>
Explanation:
<u>Speed vs Velocity
</u>
These are two similar physical concepts. They only differ in the fact that the velocity is vectorial, i.e. having magnitude and direction, and the speed is scalar, just the magnitude regardless of the direction. They are strongly related to the concepts of displacement and distance, which are the vectorial and scalar versions of the space traveled by a moving object. The velocity can be computed as
![\displaystyle \vec v=\frac{\vec r}{t}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cvec%20v%3D%5Cfrac%7B%5Cvec%20r%7D%7Bt%7D)
Where
is the position vector and t is the time. The speed is
![\displaystyle v=\frac{d}{t}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20v%3D%5Cfrac%7Bd%7D%7Bt%7D)
To compute
, we only need to know the initial and final positions and subtract them. To compute d, we need to add all the distances traveled by the object, regardless of their directions.
Maggie walks to a friend's house, located 1500 meters from her place. The initial position is 0 and the final position is 1500 m. The displacement is
![\vec r=1500\ m \text{ to the south}](https://tex.z-dn.net/?f=%5Cvec%20r%3D1500%5C%20m%20%5Ctext%7B%20to%20the%20south%7D)
and the velocity is
![\displaystyle \vec v=\frac{1500}{45}=33.33\ m/s\text{ to the south}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cvec%20v%3D%5Cfrac%7B1500%7D%7B45%7D%3D33.33%5C%20m%2Fs%5Ctext%7B%20to%20the%20south%7D)
Now, we know Maggie had to make three different turns of direction to finally get there. This means her distance is more than 1500 m. Let's say she walked 500 m in all the turns, then the distance is
![d=1500+500=2000\ m](https://tex.z-dn.net/?f=d%3D1500%2B500%3D2000%5C%20m)
If she took the same time to reach her destiny, she would have to run faster, because her average speed is
![\displaystyle v=\frac{2000}{45}=44.44\ m/s](https://tex.z-dn.net/?f=%5Cdisplaystyle%20v%3D%5Cfrac%7B2000%7D%7B45%7D%3D44.44%5C%20m%2Fs)
<span>What I have here is exactly the same problem, however, with the time changed to 19 mins:
metabolic energy = metabolic power*time = 1.150*19*60 = 1.311 kJ..corresponding to 1.311/4.186 = 313,2 Cal or kcal
If we reasonably assume a metabolic eff.cy of 20%, it means we need to assume food for 1500 Cal approx.
Just plug the value t=15min to the equation and you will surely get the correct answer.
I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!
</span>
F-free = m*g - F_air = m*a
F_air = 1.2 * m
a= (105 kg * 9.8 m.s^2 - 5*105) / 105 kg
a = 9.3 m/s
Hope this helps
They use Newton to measure force