Answer:
A. False, frequency can increase or decrease wavelength.
For example: a high frequency would mean there are shorter wavelengths that occur in a period. Meanwhile, a low frequency would indicate that the wavelengths are longer and in longer periods.
Answer:
d= 794.4 cmExplanation:
Given that
Speed ,V= 286 km/h

V=79.44 m/s
Given that time ,t= 100 ms
t= 0.1 s
We know that ( if acceleration is zero)
Distance = Speed x time
d= V t
Now by putting the values in the above equation
d = 79.44 x 0.1 m
d= 7.944 m
We know that 1 m = 100 cm
d= 794.4 cm
Answer:
Explanation:
Caty , Use the relativity formula for length. ( they teach this in H.S. ? ) it's from my Modern Physics in college, A 300 level class
L = 

L = 3 
L = 0.9367496998 meters
L = 0.94 meters approx
Answer:
2633.7 s
Explanation:
From the question,
Heat lost by the water heater = Heat gained by the water
Applying,
P = cm(t₂-t₁)/t.................. Equation 1
Where P = power of the heat, c = specific heat capacity of water, m = mass of water, t₁ = initial temperature, t₂ = final temperature, t = time
make t the subject of the equation
t = cm(t₂-t₁)/P.............. Equation 2
From the question,
Given: c = 4190 J/kgK, P = 3.5 kW = 3500 W, m = 40 kg, t₁ = 20°C, t₂ = 75°C
Substitute these values into equation 2
t = 4190×40(75-20)/3500
t = 9218000/3500
t = 2633.7 s