Nitrogen and phosphorus !
Answer:
D
Explanation:
D) The overall work done by gravity is zero
This statement is correct .
If m be the mass of each of the children and h be the height of tower
work done by gravity on the boys in going up = - mgh
it is so because force applied by gravity = mg downwards and displacement
is upwards
work done will be negative = - mgh
Work done by gravity on boys when they come down = + mgh because both force and displacement are downwards .
Hence total work done = - mgh + mgh = 0.
The children will have same kinetic energy as the inclined surface is friction-less so no energy will be dissipated hence addition of energy to boys in both the cases will be same.
The apparent magnitude scale is a classification scheme which is based on the brightness of stars. The range of brightness values is from 1 to 6.
The stars which are the most brightest are ranked as number 1 and also called first magnitude stars, stars which are little dimmer than number 1 are ranked as number 2 and also called second magnitude stars. Similarly the most faintest stars are ranked number 6 and also called as the sixth magnitude stars.
The answer would be flood basalt. This is the outcome
of a huge volcanic eruption or sequence of eruptions that covers large expanses
of land or the ocean floor with basalt lava. The development and
effects of a flood basalt hinge on a variety of factors, like latitude, continental
configuration, rate, volume, period of eruption, the preexisting climate
state, style and location, and the biota flexibility to alteration.
<u>Answer</u>
B•Horizontal=11.49 m/s
Vertical=9.64 m/s
Using the concept of a trigonometric ratios,
sin θ = y/hypotenuse
where y is the vertical component.
sin 40 = y/15
y = 15 × sin 40
= 9.64 m/s
vertical component = 9.64 m/s
cos θ = x/hypotenuse
where x is the horizontal component
cos 40 = x/15
x = 15 × cos 15
=11.49
Horizontal component = 11.49 m/s