Electromagnetic waves are those waves that are composed of electric and magnetic fields perpendicular to each other and to the direction of the propagation. All electromagnetic waves have the same speed.
That is, 3×10⁸ m/s.
X-ray is one of the electromagnetic waves. So are light, gamma rays, and radio waves.
Thus the speed of all these waves is equal.
Thus, the correct answer is option C, "Same as speed of radio waves"
Answer:
(a) 1058.4 J
(b) -10584 J
Explanation:
Parameters given:
Mass of astronaut, m = 72 kg
Distance moved by astronaut, d = 15 m
(a) WORK DONE BY FORCE FROM THE HELICOPTER
Work done is given as the product of Force applied to a body and the distance moved by the body:
W = F * d
The force from the helicopter is given as:
F = m * a
where a = acceleration of the astronaut due to the helicopter
Therefore, the work done is given as:
W = m * a * d
W = 72 * g/10 * 15
W = 
W = 1058.4 J
(b) WORK DONE BY FORCE OF GRAVITY
W = F * d
The force of gravity is given as:
F = -m * g
where g = acceleration due to gravity
The negative sign is due to the fact that the astronaut moves in an opposite direction (upwards) to the force of gravity (Gravity acts downwards)
Therefore, the work done is given as:
W = -m * g * d
W = -72 * 9.8 * 15
W = -10584 J
Answer:
dopamine is used to help with Parkinson
Explanation:
D. dopamine
Answer:
Explanation:
specific heat of marble is 880 J/kg °C
specific heat of brass is 920 J/kg °C
If Q heat is given to a body of mass m and specific heat s , and there is a rise of temperature t
Q = m s t
t = Q / m s
if Q and m is constant
t is inversely proportional to specific heat .
so rise in temperature will be inversely proportional to specific heat .
lower the specific heat , higher will be the rise in temperature . Since marble has lower specific heat , rise in temperature in marble will be higher and quicker .
So brass will take longer time to warm up.
I think the correct answer is C. Volcanoes are formed in subduction zones or in rift valleys. They are formed when hot magma within the upper mantle of the Earth would work way up the surface. As it reaches the surface, an eruption would happen forming lava flows and deposits of ash. As it continues to erupt, it would grow bigger and bigger. These would form commonly in divergence or convergence tectonic plates. On Earth, there are about 1500 volcanoes that are active. About 80 of these can be found under the oceans. The active ones are mostly found in washington, oregon, alaska, california and hawaii.
