Answer:
25 seconds
Explanation:
Assuming the woman is accelerating at a constant rate of
from the initial velocity, u=4.20 m/s, to the final velocity, v=5.00 m/s.
Let she takes t seconds to cover the distance, s=115 m.
As acceleration, ![a=\frac{v-u}{t}=\frac{5-4.2}{t}](https://tex.z-dn.net/?f=a%3D%5Cfrac%7Bv-u%7D%7Bt%7D%3D%5Cfrac%7B5-4.2%7D%7Bt%7D)
![\Rightarrow at=0.8\cdots(i)](https://tex.z-dn.net/?f=%5CRightarrow%20at%3D0.8%5Ccdots%28i%29)
Now, from the equation of motion
![s=ut+\frac 12 at^2](https://tex.z-dn.net/?f=s%3Dut%2B%5Cfrac%2012%20at%5E2)
![\Rightarrow s=ut+\frac 12 at(t)](https://tex.z-dn.net/?f=%5CRightarrow%20s%3Dut%2B%5Cfrac%2012%20at%28t%29)
[ from equation (i)]
![\Rightarrow 115=(4.2+0.4)t](https://tex.z-dn.net/?f=%5CRightarrow%20115%3D%284.2%2B0.4%29t)
seconds.
Hence, she takes 25 seconds to walk the distance.
Answer:
D is the answer
Explanation:
6.45×7.44= 47.98800
Which if we round of we get 48m
Since like poles repel, the two horseshoe magnets have like poles facing each other, hence they repel each other and therefore they will not come in contact
Answer:
0.44807175m
Explanation:
k = Spring constant =
(Assumed, as it is not given)
g = Acceleration due to gravity = 9.81 m/s²
Total mass is
![m=26\times 67+3\times 15+5\times 3+25\\\Rightarrow m=1827\ kg](https://tex.z-dn.net/?f=m%3D26%5Ctimes%2067%2B3%5Ctimes%2015%2B5%5Ctimes%203%2B25%5C%5C%5CRightarrow%20m%3D1827%5C%20kg)
The total weight will balance the spring force
![mg=kx\\\Rightarrow x=\dfrac{mg}{k}\\\Rightarrow x=\dfrac{1827\times 9.81}{4\times 10^{4}}\\\Rightarrow x=0.44807175\ m](https://tex.z-dn.net/?f=mg%3Dkx%5C%5C%5CRightarrow%20x%3D%5Cdfrac%7Bmg%7D%7Bk%7D%5C%5C%5CRightarrow%20x%3D%5Cdfrac%7B1827%5Ctimes%209.81%7D%7B4%5Ctimes%2010%5E%7B4%7D%7D%5C%5C%5CRightarrow%20x%3D0.44807175%5C%20m)
The springs are compressed by 0.44807175m