Answer:
the angle of incidence θ is 45.56 º
Explanation:
Given data
strikes the mirror before wall x = 30.7 cm
reflected ray strikes the wall y = 30.1 cm
to find out
the angle of incidence θ
solution
let us consider ray is strike at angle θ so after strike on surface ray strike to wall at angle 90 - θ
we will apply here right angle triangle rule that is
tan( 90 - θ) = y /x
tan( 90 - θ) = 30.1 / 30.7
90 - θ = tan^-1 (30.1/30.7)
90 - θ = 44.4345
θ = 45.56 º
the angle of incidence θ is 45.56 º
Answer: I think the answer is d
Explanation: sry if wrong
Answer:
a) 725.5 m
b) 630 m
Explanation:
Given data:
acceleration of Helicopter = 7.0 m/s^2
time spent upwards by helicopter = 11.0 seconds
a) Determine the maximum height above ground reached by the helicopter
h1 = at^2 /2
= 7 * 11^2 / 2
= ( 7 * 121 ) / 2 = 423.5 m
also v = a*t = 7 * 11 = 77 m/s
also we calculate h2
h2 = v^2 / 2g
= (77^2) / 2 * 9.81
= 302 m
therefore the maximum height = 302 + 423.5 = 725.5 m
b) Given that ; power deploys a jet pack strapped on his back at 7.0 s and with a downward acceleration of ; 1.0 m/s^2
<u>Determine distance Power reaches before helicopter crashes </u>
s = ut + 1/2 at^2
h.gt^2 - 77t - 423.5 m = 0
h.gt^2 - 77t = 423.5
t = 17. 66 secs
Yf = 423.5 + 77 *7 - 4.9 *7
Yf = 928.2
Vf = u + at
= 77 - 9.8*7 = 8.4 m/secs
t' = 17.66 - 7 = 10.66 secs
hence
Yf = 725.5 - 8.4 * 10.66 + 1/2 * -1 * 10.66
= 630 meters
The kinetic energy of the bullet is 20.4 kJ.
<u>Explanation:</u>
Kinetic energy of a bullet will be equal to the product of mass of the bullet with the square of velocity or speed of the bullet and then the half of that product value.
But here the mass of the bullet is not given, instead the weight of the bullet is given in terms of force. So from this, we have to first find the mass of the bullet.
We know that as per Newton's second law of motion, force is directly proportional to the product of mass and acceleration. So here the acceleration will be equal to the acceleration due to gravity as it is weight of the object.
So F = mg
0.10 N = m × 9.8
So ,the mass of the bullet is 0.0102 kg.
Now, we know the mass and velocity of the bullet is given as 2000 m/s.
So,
kinetic energy =
× m × v²
kinetic energy = 0.5 × 0.0102 × 2000 × 2000 = 20.4 kJ
Thus, the kinetic energy of the bullet is 20.4 kJ.