Explanation:
Newton’s second law of motion is closely related to Newton’s first law of motion. It mathematically states the cause and effect relationship between force and changes in motion. Newton’s second law of motion is more quantitative and is used extensively to calculate what happens in situations involving a force. Before we can write down Newton’s second law as a simple equation giving the exact relationship of force, mass, and acceleration, we need to sharpen some ideas that have already been mentioned.
First, what do we mean by a change in motion? The answer is that a change in motion is equivalent to a change in velocity. A change in velocity means, by definition, that there is an acceleration. Newton’s first law says that a net external force causes a change in motion; thus, we see that a net external force causes acceleration.
Answer:
First one, third one, and fourth one
Answer:
The frequency of wave is 160Hz.
Explanation:
Given that the formula of speed is V = f×λ where V represents speed, f is frequency and λ is wavelength.
So first thing, you have to make frequency the subject by dividing wavelength on both sides :



Next you have to substitute the value of v and f into the formula :
Let λ = 2.5m,
Let v = 400m/s,


Answer:
T = 692.42 N
Explanation:
Given that,
Mass of hammer, m = 8.71 kg
Length of the chain to which an athlete whirls the hammer, r = 1.5 m
The angular sped of the hammer, 
We need to find the tension in the chain. The tension acting in the chain is balanced by the required centripetal force. It is given by the formula as follows :

So, the tension in the chain is 692.42 N.
The photoelectric effect is obtained when you shine a light on a material, resulting in the emission of electrons.
The kinetic energy of the electrons depends on the frequency of the light:
K = h(f - f₀)
where:
K = kinetic energy
h = Planck constant
f = light frequency
f₀ = threshold frequency
Rearranging the formula in the form y = m·x + b, we get:
K = hf - hf₀
where:
K = dependent variable
f = <span>indipendent variable
h = slope
hf</span>₀ = y-intercept
Every material has its own threshold frequency, therefore, what stays constant for all the materials is h = Planck constant (see picture attached).
Hence, the correct answer is
C) the slope.