Answer:
1331.84 m/s
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity = 0
s = Displacement = 490 km
a = Acceleration
g = Acceleration due to gravity = 1.81 m/s² = a
From equation of linear motion

The speed of the material must be 1331.84 m/s in order to reach the height of 490 km
The surface or material that underlies a two-dimensional work of art is called the support.
Explanation:
Ummm i think a timer or clock?
Answer:
Surely Achilles will catch the Tortoise, in 400 seconds
Explanation:
The problem itself reduces the interval of time many times, almost reaching zero. However, if we assume the interval constant, then it is clear that in two hours Achilles already has surpassed the Tortoise (20 miles while the Tortoise only 3).
To calculate the time, we use kinematic expression for constant speed:

The moment that Achilles catch the tortoise is found by setting the same final position for both (and same time as well, since both start at the same time):

Answer:
3.28 degree
Explanation:
We are given that
Distance between the ruled lines on a diffraction grating, d=1900nm=
Where 


We have to find the angular width of the gap between the first order spectrum and the second order spectrum.
We know that

Using the formula
m=1


Now, m=2





Hence, the angular width of the gap between the first order spectrum and the second order spectrum=3.28 degree