Answer:
Explanation:
for the unit vector, we need to divide the given vector by its norm, because it should be in the SAME direction as the original vector, but of magnitude "1".
We notice that the norm of the given vector is:
Then, the unit vector becomes:
Consider a long train moving at speed v. Now consider a passenger throwing a ball inside this train, towards the back of the train, with same velocity v (but in the opposite direction of the train movement).
- A passenger inside the train will see the ball moving with speed v
- For an observer outside the train, however, the ball will appear as still. In fact, for him the ball will have a speed v (given by the movement of the train) -v (velocity of the ball but moving in the opposite direction), so the net velocity will be v+(-v)=0.
Explanation:
Calculating this according to the m/s rate
Now solving the question
If the car goes 20 m/s mathematically we can generate it as
15 × 60 = 600 secs
If the car goes 20 meters per every second it means
The car will go 20 meters for 900 secs
Which is 900 ×20 = 18000m/s
=18000÷1000 = 1km
Therefore the answer is 18km
Answer:
Explanation:
The magnitude of the electric field between two parallel conducting plates is defined as:
Here 
is the potential difference between the plates and d its separation.
The electric potential energy is defined as the product between the particle's charge and the potential difference:
Solving for and replacing in the electric field formula:
In this case we have a double charged ion, so 
:
