Answer:
Explanation:
<u>Vertical Launch Upwards</u>
In a vertical launch upwards, an object is launched vertically up from a height H without taking into consideration any kind of friction with the air.
If vo is the initial speed and g is the acceleration of gravity, the maximum height reached by the object is given by:
The object referred to in the question is thrown from a height H=0 and the maximum height is hm=77.5 m.
(a)
To find the initial speed we solve for vo:
(b)
The maximum time or the time taken by the object to reach its highest point is calculated as follows:
Answer:
Explanation:
Force between two charges is given by the following expression
F = 
Q₁ and Q₂ are two charges and d is distance between two.
.1 =
If Q₁ becomes three times , force will become 3 times . Hence force becomes .3 N in the first case.
Force F = .3 N
If charge becomes one fourth , force also becomes one fourth .
F= 
= .025 N.
<span>The cation is positively charged and has a charge twice that of the anion, for example +2.
The anion is negatively charged and in our example where the cation has a +2 charge, it must have a -1 charge.
In order for the charges to equal zero, there must be two anions: -1 x 2 = -2
So the answer is D. AX2</span>
Answer:
274N 0.41
Explanation:
As he is sliding down in a constant speed then the force that accelerates him (weight) and the force that slows his down (friction) are equal.
then
<em>friction=mass x gravity x sin(21)</em>
Fr=78kg x 9.8m/s2 x sin(21)=274N
<em>friction= coefficient of kinetic friction x normal force of from the slope</em>
Fr= u x 78kg x 9.8m/s2 x cos(21)=274N
Fr= u x 78kg x 9.8m/s2 x cos(21)=274Nu=274/677=0.41
