Answer:
option A
Explanation:
given,
Length of boat = 4 m
width of boat = 2 m
height up to which water is displaced = 1 m
Volume of water displaced by the boat
V = L x B x H
V = 4 x 2 x 1
V = 8 m³
buoyant force acting on the boat
F_b = ρ g V
m g = ρ g V
m = ρ V
ρ is the density of water which is equal to 1000 Kg/m³
m = ρ V
m =1000 x 8
m = 8000 Kg
hence, mass of the boat is equal to 8000 Kg
so, the correct answer is option A
Answer:
1/Re=1/R1 +1/R2= 2x1/R1=2/R1=2/R2=2/50=1/25
1/Re=1/25, so the answer is Re= 25
the answer is A. 25.0
A testing instrument that's used to measure electrical signals
in a circuit and display them as waveforms on a screen is called
an oscilloscope.
Answer:
v = 14 m/s
= 31.3 mph
The answer would be the same if the mass of the car were 2000 kg
Explanation:
Let V be the final velocity of the car after skidding, and v be the initial velocity of the car. Let a be the acceleration of the car and Δx be the distance the car travels after applying brakes (length of the skid marks). Let Fk be the force of friction between the tyres and the road. Let N be the normal force exerted on the car and μ be the co efficient of kinetic friction.
V^2 = v^2 + 2×a×Δx
Now V, the final velocity is zero as the car stops
0 = v^2 + 2×a×Δx
v^2 = -2×a×Δx
v =√-2×a×Δx .....*
Now applying Newton's Second Law
Fnet = m×a
-Fk = m×a
-μ×N = m×a
-μ×m×g = m×a (The mass cancels out)
a = -μ×g
Substituting the value of a back to equation *
v = √-2×(-μ×g)×Δx
v = √-2×(-0.5×9.8)×20
v = 14 m/s
Therefore the speed the car was travelling with v = 14 m/s
which is equal to 31.3 mph
Now if you were to change the mass of the car to 2000 kg the value for v would still be the same. As it is seen above mass cancels out so it does not influence or affect the value of the velocity obtained.
The human eye is one of the most valuable sense organ. The closest object that a typical young person with normal vision can focus closest to is 25 cm
The lens in the eye forms the image on the retina. The image formed is real and inverted. The retina is a very delicate membrane containing numerous light sensitive cells.
This light sensitive cells gets activated when light falls on it and generates electric signals. These electric signals are sent to the brain via the optic nerves present in the eye. The brain finally processes these signals and thus we see the object clearly.
The ability of the lens of the eye to adjust its focal length accordingly is called the power of accommodation,
The minimum distance, at which the object can be seen clearly without any strain is called the least distance of distinct vision.
To see an object clearly without any strain is when we place it at about 25 cm from the eye.
Tolearn more about optics of the eye : brainly.com/question/22371574
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