Answer:
θ = ω0 t + 1/2 ω t^2 = 1/2 α t^2 since it starts from rest
α = (15000 / 60) / 240 = 250 / 240 = 1.04 rev/sec^2
Note that α is in rev/sec^2
T(otal) = 1/2 * 1.04 * 240^2 = 30,000 revolutions
Check:
Average RPM = (15000/2) = 7500 rev/min = 125 / sec
125 / sec * 240 sec = 30,000 rev
Answer:
size of popcorn seed may meet the scaled earth size of x = 0.07312 in.
Explanation:
Given:-
- The diameter of actual sun, Ds = 1.3927 * 10^6 km
- The diameter of model sun ball, ds = 8 in
- The diameter of the actual earth, De = 12,742 km
Find:-
How large would be the earth model
Solution:-
- We can use the actual diameters of the earth and sun to develop the ratio of earth diameter to that of sun. The direct ratio can be used to model the diameter of earth for the scale model
Sun Earth
Actual : 1392700 km 12,742 km
Scale : 8 in x
- Use direct relations and solve for x:
x = (8 in)*(12,742 km ) / ( 1392700 km )
x = 0.07312 in.
- From the given options apple, grapefruit and marble diameters are larger than 1 inch. So only the size of popcorn seed may meet the scaled earth size of x = 0.07312 in.
Answer:
i believe is d
Explanation:but i’m not 100 percent sure
After 2.5 seconds of free fall, an item will be moving downhill at a speed of 25 m/s.Option D is correct.
<h3>What is velocity?</h3>
The change of displacement with respect to time is defined as speed. Speed is a scalar quantity. It is a time-based component. Its unit is m/sec.
The given data in the problem is;
t(time)= 2.5 s
u(falling velocity)=0 m/sec
v(striking velocity)=? (m/sec)
Newton's first equation of motion:
v=u+at
v=u+gt
v=10 × 2.5
v= 25 m/s downward(+ ve taken as downward)
The velocity of an object that has been in free fall for 2.5 s will be 25 m/s downward.
Hence, option D is correct.
To learn more about the velocity refer to the link;
brainly.com/question/862972
#SPJ1
Answer:
magnitude
Direction
Opposite to the velocity of aircraft
Explanation:
As we know that the initial speed of the aircraft when it land on the ground is
now the final speed of the aircraft when it covers 705 m on runway is given as
so here we know that
so now we can say that