To solve this problem we will apply the concepts related to the conservation of momentum. Momentum is defined as the product between mass and velocity of each body. And its conservation as the equality between the initial and final momentum. Mathematically described as

Here
= Mass of big fish
= Mass of small fish
= Velocity of big fish
= Velocity of small fish
= Final Velocity
The big fish eats small fish and the final velocity is zero. Rearrange the equation for the initial velocity of small fish we have


Replacing we have,


The negative sign indicates that the small fish is swimming in the direction opposite to that of the big fish.
Therefore the speed of the small fish is 10m/s
Answer:

Explanation:
Given that,
A radio wave transmits 38.5 W/m² of power per unit area.
A flat surface of area A is perpendicular to the direction of propagation of the wave.
We need to find the radiation pressure on it. It is given by the formula as follows :

Where
c is speed of light
Putting all the values, we get :

So, the radiation pressure is
.
Answer:
Oppositely charged objects attract each other
The launch velocity of the marble launcher is 34.65 m/s
Given that the launch velocity of marble launcher, launches a 25g marble to a distance of 73 cm (0.73 m) and the marble roll up to 6.2 meters before stopping. The launch height is 20 cm (0.2 m).
The time for landing can be calculated by the second equation of motion formula:
h = ut +
g
Let u = 0
0.2 = 0×t +
× 9.8 × 
= 
= 0.04
t = 0.2s
Now, the launch velocity of the marble launcher can be calculated by:
Speed = Distance / Time
Speed = 
Speed = 
Speed = 34.65 m/s
Therefore, the launch velocity of the marble launcher is 34.65 m/s
Know more about Launch velocity: -brainly.com/question/18883779
#SPJ9