A concave mirror is a curved mirror that bulges inward. Objects reflected in concave mirrors often appear bigger than they really are, although the specifics of how the image appears depends upon the object's distance from the mirror. Concave mirrors are used in car headlights, in dentist's offices and in makeup mirrors.
Answer:3.95 m/s
Explanation:
Given
radius of circle 
Water will not spill if the centripetal acceleration is greater than acceleration due to gravity
i.e. 
Answer:
12 m/s
Explanation:
Using the continuity equation, which is an extension of the conservation of mass law
ρ₁A₁v₁ = ρ₂A₂v₂
where 1 and 2 indicate the conditions at two different points of flow, in this case, point 1 is any normal position in the pip and point 2 is the conditions at the restriction.
ρ = density of the fluid flowing; note that the density of the fluid flowing (water) is constant all through the fluid's flow
A₁ = Cross sectional Area of the pipe at point 1 = (πD₁²/4)
A₂ = Cross sectional Area of the pipe at the restriction = (πD₂²/4)
v₁ = velocity of the fluid flowing at point 1 = 3 m/s
v₂ = velocity of the fluid flowing at The restriction = ?
ρ₁A₁v₁ = ρ₂A₂v₂
Becomes
A₁v₁ = A₂v₂ (since ρ₁ = ρ₂)
(πD₁²/4) × 3 = (πD₂²/4) × v₂
3D₁² = D₂² × v₂
But
D₂ = (D₁/2)
And D₂² = (D₁²/4)
3D₁² = D₂² × v₂
3D₁² = (D₁²/4) × v₂
(D₁²/4) × v₂ = 3D₁²
v₂ = 4×3 = 12 m/s
Answer:
Electromagnetic waves can travel through empty space.
Explanation:
Electromagnetic waves are defined as the waves that are created due to the vibrations between a magnetic field and an electric field.
Earth atmosphere is made up of several gases and spaces between them. Thermal energy from the sun require to pass through space by electromagnetic radiation. Electromagnetic waves can travel through empty space and that is why other type of waves are unable to transfer thermal energy.
Hence, the correct answer is "Electromagnetic waves can travel through empty space".
Answer:
5.59 m/s2
Explanation:
F = 1900 N
m = 340 kg
F = ma
Therefore, a = 1900/340 = 5.59
