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
Answer:
The radius of the slave piston = 14.10 cm
Explanation:
The formula to apply here is that for pressure where ;
Pressure = Force / Area
F₁ /A₁ =F₂/A₂ where ; F₁=200 N , A₁= 25 cm² , F₂ =5000 N ,A₂ =?
Apply values in the equation as ;
200/ 25 = 5000/ A₂
A₂ = 625 cm²
Formula for area is ;
A = πr²
625 = π * r²
625/π = r²
√625/π =r
14.10 cm = r
When moving with the current, the speeds of the boat and current will add up. The first situation can then be represented by:
9 = 0.5(x + y)
While opposing the current, the speeds will be subtracted. Forming:
9 = 1.5(x - y)
The second option contains this equation system, so it is correct.
Http://www.kyrene.org/cms/lib2/AZ01001083/Centricity/Domain/2932/Peppered%20Moth%20and%20Galapados%20Island%20PowerPoint.pptx
This should lead you to correct answer