Answer:
frequency = 0.5 Hz and speed = 2 m/s
Explanation:
Given that,
The period of a wave, T = 2 s
Wavelength, 
If f be the frequency. So,
f = 1/T

Speed of a wave is given by :

So, the frequency of the wave is 0.5 Hz and speed is 2 m/s.
Answer:
7500 m
Explanation:
The radar emits an electromagnetic wave that travels towards the object and then it is reflected back to the radar.
We can call L the distance between the radar and the object; this means that the electromagnetic wave travels twice this distance, so
d = 2L
In a time of

Electromagnetic waves travel in a vacuum at the speed of light, which is equal to

Since the electromagnetic wave travels with constant speed, we can use the equation for uniform motion ,so:
(1)
where


, where L is the distance between the radar and the object
Re-arranging eq(1) and substituting, we find L:

Use Newton's second law to determine the acceleration being applied to the sled. There are three forces at work on the sled (its weight, the force normal to the ground, and friction) but two of them cancel, leaving friction as the only effective force. This vector is pointed in the opposite direction of the sled's movement, so if we take the direction of its movement to be the positive axis, we would find the acceleration due to the friction to be

Now we use the formula

to find the distance it travels. The sled comes to a rest, so
, and let's take the starting position
to be the origin. Then the distance traveled
is

Answer:
371.2 mm
Explanation:
The Balmer series of spectral lines is obtained from the formula
1/λ = R(1/2² -1/n²) where λ = wavelength, R = Rydberg's constant = 1.097 × 10⁷ m⁻¹
when n = 15
1/λ = 1.097 × 10⁷ m⁻¹(1/2² -1/15²)
= 1.097 × 10⁷ m⁻¹(1/4 -1/225)
= 1.097 × 10⁷ m⁻¹(0.25 - 0.0044)
= 1.097 × 10⁷ m⁻¹ 0.245556
= 2.693 10⁶ m⁻¹
So,
λ = 1/2.693 10⁶ m⁻¹
= 0.3712 10⁻⁶ m
= 371.2 mm
The pressure increase at the bottom of the pool after they enter the pool and float is 106.103 Pa.
<h3>What is absolute pressure?</h3>
Absolute pressure is the force that exists in a space when there is no matter present, or when there is a perfect vacuum. This absolute zero serves as the baseline for measurements in absolute pressure. The measurement of barometric pressure is the greatest illustration of an absolute referenced pressure. In order to determine absolute pressure, a complete vacuum is used. In contrast, gauge pressure is the amount of pressure that is measured in relation to atmospheric pressure, also referred to as barometric pressure.
given,
diameter = 6 m
depth = h = 1.5 m
Atmospheric pressure = P₀ = 10⁵ Pa
a) absolute pressure
P = P₀ + ρ g h
P = 10⁵ + 1000 x 10 x 1.5
P = 1.15 x 10⁵ Pa
b) When two person enters into the pool,
mass of the two person = 150 Kg
weight of water level displaced exists equal to the weight of person.




Area of pool 


Height of the water rise



P = ρ g h
P = 1000 x 10 x 0.0106
P = 106.103 Pa
To learn more about absolute pressure refer to:
brainly.com/question/17200230
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