It is incorrect to say heavy objects sink in water because based on the density of the water it can actually cause the "heavy object" to float, out weighing it.
Answer:
The position is 8.18cm from the mirror.
Nature is b=virtual
Size is 1.82cm
Explanation:
Note that for a convex mirror, the image distance and the focal length are negative;
Given
Object height H0 = 4cm
object distance u = 18cm
Radius of curvature R = 30cm
Since f = R/2
f = 30/2
f = -15cm
Recall that:

Since the image distance is negative, this shows that the image is a virtual image.
To get the size:

Answer:
Remains the same
Explanation:
The speed of waves of higher and lower frequency both will be same.
the speed of sound in a medium is constant and independent of it's frequency. Moreover, when the frequency changes wavelength changes accordingly, such that their product remains constant.
we know that
υ×λ = constant = velocity
υ= frequency
λ= wavelength.
Answer:
History
Explanation:
Im. Sorry. Im. Not. Much. Help