Answer:
d) The speed of the astronaut
Explanation:
The sentence describes the speed of the astronaut. This speed value is 10meters per minute.
Now let us understand why;
- Speed is the distance divided by time. It is a scalar quantity without regard for direction but it has magnitude.
- The value 10meters per minute clearly shows this instance. We do not know the direction the astronaut is moving towards.
- Velocity, like speed is the displacement of a body with time. It is a vector quantity and it shows the direction of motion.
- For example, 10m/s due west is a velocity value because we know the direction.
Therefore, since there is no directional sense, the value indicates speed.
Answer:
131.25
Explanation:
i worked it out on a diffrent sheet so its hard to explain
Answer:
Electric field acting on the electron is 127500 N/C.
Explanation:
It is given that,
Mass of an electron, ![m=9.11\times 10^{-31}\ kg](https://tex.z-dn.net/?f=m%3D9.11%5Ctimes%2010%5E%7B-31%7D%5C%20kg)
Charge on electron, ![q=1.6\times 10^{-19}\ C](https://tex.z-dn.net/?f=q%3D1.6%5Ctimes%2010%5E%7B-19%7D%5C%20C)
Initial speed of electron, u = 0
Final speed of electron, ![v=3\times 10^7\ m/s](https://tex.z-dn.net/?f=v%3D3%5Ctimes%2010%5E7%5C%20m%2Fs)
Distance covered, s = 2 cm = 0.02 m
We need to find the electric field required. Firstly, we will find the acceleration of the electron from third equation of motion as :
![a=\dfrac{v^2-u^2}{2s}](https://tex.z-dn.net/?f=a%3D%5Cdfrac%7Bv%5E2-u%5E2%7D%7B2s%7D)
![a=\dfrac{(3\times 10^7)^2-0}{2\times 0.02}](https://tex.z-dn.net/?f=a%3D%5Cdfrac%7B%283%5Ctimes%2010%5E7%29%5E2-0%7D%7B2%5Ctimes%200.02%7D)
![a=2.25\times 10^{16}\ m/s^2](https://tex.z-dn.net/?f=a%3D2.25%5Ctimes%2010%5E%7B16%7D%5C%20m%2Fs%5E2)
According to Newton's law, force acting on the electron is given by :
F = ma
![F=9.1\times 10^{-31}\times 2.25\times 10^{16}](https://tex.z-dn.net/?f=F%3D9.1%5Ctimes%2010%5E%7B-31%7D%5Ctimes%202.25%5Ctimes%2010%5E%7B16%7D)
![F=2.04\times 10^{-14}\ N](https://tex.z-dn.net/?f=F%3D2.04%5Ctimes%2010%5E%7B-14%7D%5C%20N)
Electric force is given by :
F = q E, E = electric field
![E=\dfrac{F}{q}](https://tex.z-dn.net/?f=E%3D%5Cdfrac%7BF%7D%7Bq%7D)
![E=\dfrac{2.04\times 10^{-14}}{1.6\times 10^{-19}}](https://tex.z-dn.net/?f=E%3D%5Cdfrac%7B2.04%5Ctimes%2010%5E%7B-14%7D%7D%7B1.6%5Ctimes%2010%5E%7B-19%7D%7D)
E = 127500 N/C
So, the electric field is 127500 N/C. Hence, this is the required solution.
Answer:
Option A
Lowering the amount of reactants
Explanation:
To reduce the rate of chemical reaction, one can reduce temperature or surface area. The addition of catalysts increases rate of reaction but decreasing the amount of reactants decreases rate of reaction. Therefore, from the choices provided, choice A is correct.