Answer: Option B
The wavelength for a radio wave with a frequency of 2 × 10⁴ Hz is
1.5 × 10⁴ m.
Explanation:
Wavelength is the measure of distance between two successive crests or troughs in a standing wave. Also wavelength can be measured as the ratio of velocity of light to frequency. It is like this because wavelength is inversely proportional to the frequency.

As c = 3 × 10⁸ m/s and the frequency is 2 × 10⁴ Hz, then the wavelength will be

So, the wavelength for a radio wave with a frequency of 2 × 10⁴ Hz is
1.5 × 10⁴ m.
Answer: Ok, so you know the acceleration, lets call it A.
now, the velocity will take the form of V= A*t + v0, where v0 is the inicial velocity, in this case the boat starts from the rest, so v0 = 0
integrating again you obtain R = (A*t*t)/2 + r0, and we will take r0 = 0.
so, at a time t₁ we have a velocity V = v = A*t₁
R = r = (A*t₁*t₁)/2
so a t₂=2*t₁
V= A*2*t₁= 2v
R= 0.5*A*t₁*t₁*4 = 4r
so the answer is c.
Answer:
2.465Ns;1.76N
Explanation:
From Newton's Second Law:
There is a conservation of Momentum hence:
Momentum before the impact equals that after the impact.
Hence.
1. The Impulse is same as the change in Momentum which is;
0.145 ×17 =2.465Ns { note: 145g in kg is 0.145}
2. From Newton's third Law; force is the rate of change of impulse expressed mathematically as;
F = m×v / t
Where m×v is impulse and t is time given.
F = 2.465/ 1.4 = 1.76N