Answer:
The velocity of sound is greatest in option a water option be here option c vacancy option d metals.
Explanation:
(2) impulse is a vector quantity. Energy has no direction, nor does power. Work is a dot product of vector quantities, which makes it a scalar.
Answer:
Magnification m is 2.5cm
Explanation:
This problem bothers on lenses
Given data
Object distance u= 4cm
Height of object v= 10 cm
The problem is quite straightforward seeing that object and image distances are given
We know that the magnification
m= size of image/size of object
m= v/u= 10/4 = 2. 5cm
What is a convex lens
A convex lens is a type of lens that has the centre thicker than the ends, the thickness at the centre makes the lens surface to curve outward. Convex lens causes close light rays of light to converge at a point after refraction.
Answer:
69.42 m
Explanation:
From the question given above, the following data were obtained:
Initial velocity (vᵢ ) = 4.9 m/s
Acceleration (a) = 4.2 m/s²
Time (t) = 4.7 s
Displacement (Δx) =?
Thus, we can obtain the displacement by using the following formula:
Δx = vᵢt + ½at²
Δx = (4.9 × 4.7) + (½ × 4.2 × 4.7²)
Δx = 23.03 + (2.1 × 22.09)
Δx = 23.03 + 46.389
Δx = 69.419 ≈ 69.42 m
Thus, the distance travelled is 69.42 m
Distance (s) =20 m
Initial velocity =0 m/s
g=10 m/s²
By using the formula:
v²= u²+ 2as
v²=0²+ 2×10×15
v²= 300
V= 10root over 3

For calculating time,
v= u+ at
10 root over 3 = 0+ 10t
10 root over= 10t
t = 1 root over 3
t = 1.73 s

The the stone will hit the ground with a velocity of 10 root over 3 m/s in 1 root over 3 sec.