Answer:
6.216 N
Explanation:
As for Newton's second law of motion
F=ma
where F= the acting force
m=subjected mass
a= the acceleration
applying F=ma to the football
F=m*a
=0.42*14.8
=6.216 N
6.216 N of a force is supplied to the ball
Answer:![3.874 m/s^2](https://tex.z-dn.net/?f=3.874%20m%2Fs%5E2)
Explanation:
Given
Car speed decreases at a constant rate from 64 mi/h to 30 mi/h
in 3 sec
![60mi/h \approx 26.8224m/s](https://tex.z-dn.net/?f=60mi%2Fh%20%5Capprox%2026.8224m%2Fs)
![34mi/h \approx 15.1994 m/s](https://tex.z-dn.net/?f=34mi%2Fh%20%5Capprox%2015.1994%20m%2Fs)
we know acceleration is given by ![=\frac{velocity}{Time}](https://tex.z-dn.net/?f=%3D%5Cfrac%7Bvelocity%7D%7BTime%7D)
![a=\frac{15.1994-26.8224}{3}](https://tex.z-dn.net/?f=a%3D%5Cfrac%7B15.1994-26.8224%7D%7B3%7D)
![a=-3.874 m/s^2](https://tex.z-dn.net/?f=a%3D-3.874%20m%2Fs%5E2)
negative indicates that it is stopping the car
Distance traveled
![v^2-u^2=2as](https://tex.z-dn.net/?f=v%5E2-u%5E2%3D2as)
![\left ( 15.1994\right )^2-\left ( 26.8224\right )^2=2\left ( -3.874\right )s](https://tex.z-dn.net/?f=%5Cleft%20%28%2015.1994%5Cright%20%29%5E2-%5Cleft%20%28%2026.8224%5Cright%20%29%5E2%3D2%5Cleft%20%28%20-3.874%5Cright%20%29s)
![s=\frac{488.419}{2\times 3.874}](https://tex.z-dn.net/?f=s%3D%5Cfrac%7B488.419%7D%7B2%5Ctimes%203.874%7D)
s=63.038 m
Solution:
We have,
Power [P] = 25000 Watt
Mass [m] = 6000 kg
Height [h] = 20 metres
Time [t] = ?
Now,
P = W/t = F x d/t = mxgx h/t
Or, 25000 = 6000 x 10 x 20/25000 [.......g = 10
m/s^2]
Or, t = 6000 x 10 x 20/25000
Or, t = 1200/25
Therefore, t = 48 second
Hence, the required time for the crane to lift the load is 48 seconds.
Answer:
D = 18000 kg/m3
V = 2.5*10{-7}m3
Explanation:
From the Archimedes principle,
Weight of fluid displaced = W_{air} - W_{water}
W_{air} = 4.5 gm
W_{water} = 4.25 gm
![W = [4.5 - 4.25]*9.81*10^{-3}](https://tex.z-dn.net/?f=W%20%3D%20%5B4.5%20-%204.25%5D%2A9.81%2A10%5E%7B-3%7D)
W = 2.4525*10{-3} N
![\frac{density\ of\ object}{density\ of\ fluid} = \frac{weight\ in\ air}{weight\ of\ displaced\ fluid}](https://tex.z-dn.net/?f=%5Cfrac%7Bdensity%5C%20of%5C%20object%7D%7Bdensity%5C%20of%5C%20fluid%7D%20%3D%20%5Cfrac%7Bweight%5C%20in%5C%20air%7D%7Bweight%5C%20of%5C%20displaced%5C%20fluid%7D)
![Density\ of\ object = \frac{D_{water}*Weight\ in\ air}{weight\ of\ displaced\ water}](https://tex.z-dn.net/?f=Density%5C%20of%5C%20object%20%3D%20%5Cfrac%7BD_%7Bwater%7D%2AWeight%5C%20in%5C%20air%7D%7Bweight%5C%20of%5C%20displaced%5C%20water%7D)
![D = \frac{1000*4.5*10^{-3}*9.8}{2.4525*10^{-3}}N](https://tex.z-dn.net/?f=D%20%3D%20%5Cfrac%7B1000%2A4.5%2A10%5E%7B-3%7D%2A9.8%7D%7B2.4525%2A10%5E%7B-3%7D%7DN)
D = 18000 kg/m3
b) object Volume can be obtained as ,
![V = \frac{m}{D} = \frac{4.5*10^{-3}}{18000}](https://tex.z-dn.net/?f=V%20%3D%20%5Cfrac%7Bm%7D%7BD%7D%20%3D%20%5Cfrac%7B4.5%2A10%5E%7B-3%7D%7D%7B18000%7D)
V = 2.5*10{-7}m3
Answer:
Tides are very long waves that move across the oceans. They are caused by the gravitational forces exerted on the earth by the moon, and to a lesser extent, the sun. ... Because the gravitational pull of the moon is weaker on the far side of the Earth, inertia wins, the ocean bulges out and high tide occurs.
Explanation: