Answer:
Speed at which it will reach the ground is given as
Total time for which it will remain in air is given as
t = 6.3 s
Explanation:
As we know that the object is projected upwards with speed
now when it will reach the ground then we have
so we have
so we have
Now speed of the object when it reaches the ground is given as
Explanation:
It is given that,
Let Charge of 
is taken from points A & B such that 
.
We need to find the energy of charge. Electric potential is defined as the work done per unit of electric charge. So,
So, the energy of charge decreases by 
. Hence, the correct option is (a).
Answer:
Refracted rays travel through a boundary into a new medium.
Explanation:
Refracted rays travel through a boundary into a new medium. is only true for refraction.
The angle of incidence is the same for angle of refraction, is not true for refraction. Refraction follows Snell's law, states that ratio of the sine of the angle of refraction and the sine of the angle of incidence is always constant and equivalent to the ratio of phase velocities of the two mediums it is passing through.
Refracted rays change direction and go back to the original medium is false for refraction however, it is true for reflection.
Answer: The hypotenuse is 26 ft.
Step-by-step explanation: Let's call the shorter leg of the triangle x. The hypotenuse would be x + 16 and the other leg is y.
As the area is 120, we know that x.y/2 = 120 (because it's a right triangle).
This way, y = 240/x
we know that in a right triangle, we have a² = b² + c²
(x + 16)² = x² + y²
(x + 16)² = x² + (240/2)²
x² + 32x + 256 = x² + 57600/x²
32x + 256 = 57600/x²
32x³ + 256x² = 57600 (÷ 32)
x³ + 8x² = 1800
x = 10
∴
x + 16 = 26
y = 240/10 = 24
