Answer:
Explanation:
Given
Dolphin leaps out an angle 
Horizontal component of dolphin velocity 
Suppose u is the launch velocity of dolphin
therefore 
and vertical velocity 
divide 1 and 2 we get




Answer:
T2 ∝ a3
Explanation: took the quick check
Answer:
Grams of water can be heated from 20.0°C to 75°C using 12500.0 Joules = 54.3 g
Explanation:
Heat required to increase temperature
H = mcΔT
m = mass of material
C = specific heat of material
ΔT = Change in temperature.
Here we need to find how many grams of water can be heated from 20.0°C to 75°C using 12500.0 Joules
That is
H = 12500 J
Specific heat of water, C = 4186 J/kg°C
ΔT = 75 - 20 = 55
Substituting
12500 = m x 4186 x 55
m = 0.0543 kg
m = 54.3 g
Grams of water can be heated from 20.0°C to 75°C using 12500.0 Joules = 54.3 g
Answer:
R=0.5B+0.5C+2A+D
Explanation:
By the triangular law of vector addition
vector R= vector B- vector D
As A,B,C,D are edges of the parallelogram,
A is parallel to D but opposite in direction.
Therefore
;
;

B is parallel to C and in same direction.



Answer:
<h2>35</h2>
Explanation:
According to snell's law which states that the ratio of the sin of incidence (i) to the angle of refraction(n) is a constant for a given pair of media.
sini/sinr = n
n is the constant = refractive index
Since the diver shines light up to the surface of a flat glass-bottomed boat, the refractive index n = nw/ng
nw is the refractive index of water and ng is that of glass
sini/sinr = nw/ng
given i = 30°, nw = 1.33, ng = 1.5, r = angle the light leave the glass
On substitution;
sin 30/sinr = 1.33/1.5
1.5sin30 = 1.33sinr
sinr = 1.5sin30/1.33
sinr = 0.75/1.33
sinr = 0.5639
r = arcsin0.5639
r ≈35°
angle the light leave the glass is 35°