4. The diagram below shows three water wavefronts A, B and C moving from deep water to shallow water Wavefront A has just reached the boundary between the deep
water and the shallow water. Parts of wavefronts B and C have already crossed into
the shallow water. The direction of these incident wavefronts is marked and the
nomals to the boundary are marked N.
Deep water
Incident wave
direction
Shallow water
A
B
5.0 cm
(I) Use the words
Stays the same
increases
decreases
To describe what happens to the following properties of the waves as they travel
into the shallow water.
Speed
Wavelength
Frequency
[3]
Carefully complete the diagram above to show wavefronts B and C as they travel
through the shallow water
[2]
(1) The water waves are made by a long bar vibrating in the water
The long bar makes 24 vibrations in 6 seconds. Calculate the frequency of the water
waves produced. Include the unit
Frequency
(3)

B) raising the temperature and reducing the volume of the gas.|-/ 

    m₁v₁ + m₂v₂ = (m₁ + m₂)vmomentum is conserved.the left-hand side of the equation represents the momentum in the system before the collision.the right-hand side represents the momentum in the system after the collisionm₁ and v₁ represents the mass and the velocity of the physics blockm₂ and v₂ represents the mass and velocity of the ball of puttyv represents the final velocity of the combined mass.the question states the two masses stick together. they combined mass has its own velocity with the body mass the sum of the two objects' massestheir combined momentum is (m₁ + m₂)vto find the magitude of (m₁ + m₂)v, we need to add the vectors on the left-hand side of the equation: m₁v₁ + m₂v₂.note the diagram. i have positioned the vectors in accordance with their directions.the magnitude of the resultant can be calculated using the pythagorean theorem since this is a right triangle situation (north and west are perpendicular)|(m₁ + m₂)v| =  √[ (m₁v₁)² + (m₂v₂)² ]|(m₁ + m₂)v| =  √[ (1.5kg·8.0m/s)² + (0.40kg·20m/s)² ]|(m₁ + m₂)v| =  14.4 kg m/sfor two significant figures (assuming that 20m/s is two), this rounds to 14 kg m/s

The best answer i can think of is b