Answer:
a. It always points perpendicular to the contact surface.
Explanation:
"Normal" means perpendicular. Normal forces are always perpendicular to the contact surface.
Answer:
625 W
Explanation:
Applying
P = W/t.................... Equation 1
Where p = power, W = Work, t = time
But,
W = Force (F) × distance (d)
W = Fd........................ Equation 2
Substitute equation 2 into equation 1
P = Fd/t.................... Equation 3
From the question,
Given: F = 5000 N, d = 30 m, t = 4 munites = (4×60) seconds = 240 seconds
Substitute these values into equation 3
P = (5000×30)/240
P = 625 Watt
Actual Mechanical Advantage(AMA) = Weight / Force
Here, Weight = 764 N
Force = 255 N
Substitute the values in to the expression,
AMA = 764 / 255
AMA = 2.99
After rounding-off to the nearest tenth value, it would be 3
Finally, option C would be your answer.
Hope this helps!
Answer:
(D)
to establish an understanding of key concepts relating to population biology
Explanation:
Thats what I would go with but I didn't read the article so I don't know what context was used. Good luck! :)
Answer:
1,373.4 N
Explanation:
The mass of the table acts at the centre in addition to the books since that is the centre of gravity of the table.
Mass of books will be 10kg+20kg+30kg=60 kg
Total mass of table and books will be 500kg+60kg=560 kg
This mass is evenly distributed into the four legs hence 560kg/4 legs=140 kg per leg
Force is product of mass and acceleration due to gravity hence F=gm
Taking g as 9.81 m/s2 then
F=140*9.81=1,373.4 N
Therefore, rhe normal force is equivalent to 1,373.4 N