The ball can't reach the speed of 20 m/s in two seconds, unless you THROW it down from the window with a little bit of initial speed. If you just drop it, then the highest speed it can have after two seconds is 19.6 m/s .
If an object starts from rest and its speed after 2 seconds is 20 m/s, then its acceleration is 20/2 = 10 m/s^2 .
(Gravity on Earth is only 9.8 m/s^2.)
Given the following information we have 20 watermelons from mark and 10 fishes from kim therefore we add the longitude of Walmart to the latitude of sams club and end up with a total of 1,000 dish soaps then we convert that into inches which leaves us at 20,000,000 inches of cats then multiply that number to 10 giraffes and we get
1.989 × 10^30 kg and therefore the mass of the sun is 1.989 × 10^30 kg.
Answer:
![\Delta U = \frac{Qq}{4\pi\epsilon_0}(\frac{1}{r_2^2}-\frac{1}{r_1^2})](https://tex.z-dn.net/?f=%5CDelta%20U%20%3D%20%5Cfrac%7BQq%7D%7B4%5Cpi%5Cepsilon_0%7D%28%5Cfrac%7B1%7D%7Br_2%5E2%7D-%5Cfrac%7B1%7D%7Br_1%5E2%7D%29)
Explanation:
The electrostatic potential energy is given by the following formula
![U = \frac{1}{4\pi\epsilon_0}\frac{q_1q_2}{r^2}](https://tex.z-dn.net/?f=U%20%3D%20%5Cfrac%7B1%7D%7B4%5Cpi%5Cepsilon_0%7D%5Cfrac%7Bq_1q_2%7D%7Br%5E2%7D)
Now, we will apply this formula to both cases:
![U_1 = \frac{1}{4\pi\epsilon_0}\frac{Qq}{r_1^2}\\U_2 = \frac{1}{4\pi\epsilon_0}\frac{Qq}{r_2^2}](https://tex.z-dn.net/?f=U_1%20%3D%20%5Cfrac%7B1%7D%7B4%5Cpi%5Cepsilon_0%7D%5Cfrac%7BQq%7D%7Br_1%5E2%7D%5C%5CU_2%20%3D%20%5Cfrac%7B1%7D%7B4%5Cpi%5Cepsilon_0%7D%5Cfrac%7BQq%7D%7Br_2%5E2%7D)
So, the change in the potential energy is
![\Delta U = U_2 - U_1 = \frac{Qq}{4\pi\epsilon_0}(\frac{1}{r_2^2}-\frac{1}{r_1^2})](https://tex.z-dn.net/?f=%5CDelta%20U%20%3D%20U_2%20-%20U_1%20%3D%20%5Cfrac%7BQq%7D%7B4%5Cpi%5Cepsilon_0%7D%28%5Cfrac%7B1%7D%7Br_2%5E2%7D-%5Cfrac%7B1%7D%7Br_1%5E2%7D%29)
Answer:
e. 1.2 x 10²³
Explanation:
According to the problem, The current equation is given by:
![I(t)=0.88e^{-t/6\times3600s}](https://tex.z-dn.net/?f=I%28t%29%3D0.88e%5E%7B-t%2F6%5Ctimes3600s%7D)
Here time is in seconds.
Consider at t=0 s the current starts to flow due to battery and the current stops when the time t tends to infinite.
The relation between current and number of charge carriers is:
![q=\int\limits {I} \, dt](https://tex.z-dn.net/?f=q%3D%5Cint%5Climits%20%7BI%7D%20%5C%2C%20dt)
Here the limits of integration is from 0 to infinite. So,
![q=\int\limits {0.88e^{-t/6\times3600s}}\, dt](https://tex.z-dn.net/?f=q%3D%5Cint%5Climits%20%7B0.88e%5E%7B-t%2F6%5Ctimes3600s%7D%7D%5C%2C%20dt)
![q=0.88\times(-6\times3600)(0-1)](https://tex.z-dn.net/?f=q%3D0.88%5Ctimes%28-6%5Ctimes3600%29%280-1%29)
q = 1.90 x 10⁴ C
Consider N be the total number of charge carriers. So,
q = N e
Here e is electronic charge and its value is 1.69 x 10⁻¹⁹ C.
N = q/e
Substitute the suitable values in the above equation.
![N= \frac{1.9\times10^{4} }{1.69\times10^{-19}}](https://tex.z-dn.net/?f=N%3D%20%5Cfrac%7B1.9%5Ctimes10%5E%7B4%7D%20%7D%7B1.69%5Ctimes10%5E%7B-19%7D%7D)
N = 1.2 x 10²³
Answer: 3.33 m/s
Explanation:
Assuming the questions is to convert 12 km/h to meter per second (m/s), let's begin:
In order to make the conversion, we have to know the following:
![1 km=1000 m](https://tex.z-dn.net/?f=1%20km%3D1000%20m)
And:
![1 h=3600 s](https://tex.z-dn.net/?f=1%20h%3D3600%20s)
Keeping this in mind, we can make the conversion:
![12 \frac{km}{h} \frac{1000 m}{1 km} \frac{1h}{3600 s}](https://tex.z-dn.net/?f=12%20%5Cfrac%7Bkm%7D%7Bh%7D%20%5Cfrac%7B1000%20m%7D%7B1%20km%7D%20%5Cfrac%7B1h%7D%7B3600%20s%7D)
Then:
![12 \frac{km}{h}= 3.33 \frac{m}{s}](https://tex.z-dn.net/?f=12%20%5Cfrac%7Bkm%7D%7Bh%7D%3D%203.33%20%5Cfrac%7Bm%7D%7Bs%7D)