Answer:
T = 0.225 s
Explanation:
The speed of a projectile at the highest point of its motion is the horizontal speed of the projectile. Considering the horizontal motion with negligible air resistance, we can use the following formula:
where,
T = Total time of ball in air = ?
R = Horizontal distance covered = 40 m
= horizontal speed = 9 m/s
Therefore,
<u>T = 0.225 s</u>
s = displacement; u = initial velocity; t = time of motion
<h2>
All waves must ____ have to travel through
</h2>
Explanation:
Wave
It is the periodic disturbance in a medium.
Types of Wave
There are two types of wave in general depending upon their propagation through a substance.
• Mechanical
• Electromagnetic
Mechanical Wave
It is the kind of wave which needs medium to travel. For example: Sound Wave
That means sound can be heard only whenever there is presence of certain substance like water, glass, air etc .It can’t be heard in vacuum no matter how loud is the sound.
Electromagnetic Wave
Is that which can travel through medium as well as through vacuum. For example: Light
But unlike sound, light can be seen through a substance or in vacuum. That is the reason it is referred as electromagnetic wave.
Answer:
λ = 1360 m
Explanation:
Given data:
frequency of driving nails is given as 1 stroke per second mean at every 0.25 sec she hit the nails
speed of sound is given as 340 m/s
we know that the wave equation is given as
Speed = frequency × wavelength,
v = f × λ
where,
v = speed in meters/second (m/s)
f = frequency in Hertz (Hz)
substituing value to get wavelength of her driving nails
λ = 1360 m
The answer is D. Either absorbed or reflected. The reason is because if no light is being shown on the other side, the substance is not letting any light pass through. Since we do not know anything else about the substance, we do not know which one of the two it is doing. The scientist would not see any light on the detector if 100% of the light is reflected and the same thing would happen if 100% of the light was absorbed.
