Answer: Potassium(K)
Explanation:
its an alkali metal placed under sodium and its over rubidium, its also the first element of period 4
Answer:
The resultant velocity is <u>169.71 km/h at angle of 45° measured clockwise with the x-axis</u> or the east-west line.
Explanation:
Considering west direction along negative x-axis and north direction along positive y-axis
Given:
The car travels at a speed of 120 km/h in the west direction.
The car then travels at the same speed in the north direction.
Now, considering the given directions, the velocities are given as:
Velocity in west direction is, 
Velocity in north direction is, 
Now, since
are perpendicular to each other, their resultant magnitude is given as:

Plug in the given values and solve for the magnitude of the resultant.This gives,

Let the angle made by the resultant be 'x' degree with the east-west line or the x-axis.
So, the direction is given as:

Therefore, the resultant velocity is 169.71 km/h at angle of 45° measured clockwise with the x-axis or the east-west line.
Answer:
Final velocity at the top of the ramp is 6.58m/s
Explanation
Check the attachment
Answer:
μ = 0.18
Explanation:
Let's use Newton's second Law, the coordinate system is horizontal and vertical
Before starting to move the box
Y axis
N-W = 0
N = W = mg
X axis
F -fr = 0
F = fr
The friction force has the formula
fr = μ N
fr = μ m g
At the limit point just before starting the movement
F = μ m g
μ = F / m g
calculate
μ = 34.8 / (19.8 9.8)
μ = 0.18