Answer: only the third option. [Vector A] dot [vector B + vector C]
The dot between the vectors mean that the operation to perform is the "scalar product", alson known as "dot product".
This operation is only defined between two vectors, not one scalar and one vector.
When you perform, in the first option, the dot product of any ot the first and the second vectors you get a scalar, then you cannot make the dot product of this result with the third vector.
For the second option, when you perform the dot product of vectar B with vector C you get a scalar, then you cannot make the dot product ot this result with the vector A.
The third option indicates that you sum the vectors B and C, whose result is a vector and later you make the dot product of this resulting vector with the vector A. Operation valid.
The fourth option indicates the dot product of a scalar with the vector A, which we already explained that is not defined.
Answer:
34
Explanation:
The problem provides you with thesolubility of potassium chloride, KCl , in water at 20∘C , which is said to be equal to 34 g / 100 g H2O . This means that at 20∘C , a saturated solution of potassium chloride will contain 34 g of dissolved salt for every100 g of water.
Impulse = mass * change in velocity (change in momentum) = Force * change in time
So, F=(m*change in v)/(change in t)
F=(60*20)/0.5=2400N
Therefore the magnitude of the average force exerted on the cyclist by the haystack is 2.4*10^3N
Complete Question
If you are lying down and stand up quickly, you can get dizzy or feel faint. This is because the blood vessels don’t have time to expand to compensate for the blood pressure drop. If your brain is 0.4 m higher than your heart when you are standing, how much lower is your blood pressure at your brain than it is at your heart? The density of blood plasma is about 1025 kg/m3 and a typical maximum (systolic) pressure of the blood at the heart is 120 mm of Hg (= 0.16 atm = 16 kP = 1.6 × 104 N/m2).
Answer:
The pressure at the brain is 
Explanation:
Generally is mathematically denoted as

Substituting
for
(the density) ,
for g (acceleration due to gravity) , 0.4m for h (the height )
We have that the pressure difference between the heart and the brain is

But the pressure of blood at the heart is given as

Now the pressure at the brain is mathematically evaluated as



If you drop a <span>6.0x10^-2 kg ball from height of 1.0m above hard flat surface, and a</span>fter the ball had bounce off the flat surface, the kinetic energy of the ball would be mgh - 0.14 = 0.45.