The answer is -17x-1. You have to combine like terms.
Answer:
D) The velocity of the airplane must be greater than the speed of sound
Explanation:
Sonic boom is a phenomenon that occurs when an airplane travels ay a velocity greater than the speed of sound.
When this condition is met, the sound waves produced by the airplane (mainly from the engine) is not able to travel ahead of the plane, because the plane is moving at a greater speed than the sound itself; as a result, it is only transmitted behind the plane.
In this situation, a shock wave is produced. This shock wave is associated with a very loud "bang", that can be heard clearly even at several kilometers distance (in fact, supersonic planes are normally not allowed to fly over residential areas. In the past, for example the Concorde, was only allowerd to fly at supersonic speed over the ocean).
So the correct answer is
D) The velocity of the airplane must be greater than the speed of sound
The answer is 111.
Using Newton's Second Law, F=ma, plugging known values in we get:
F = (79kg)(1.4m/s^2) = 110.6N ≈ 111N
Answer:
0.003333 s to 0.000125s or from 3.33ms to 0.125ms wher m is for milli
1.1m to 0.04125 m
Explanation:
T= 1/f=
if f= 300Hz then T = 1/300 =0.003333 s
if f= 8000 then T= 1/8000 = 0.000125s
now v=f×wave length
or wavelength = speed/ frequency
when f = 300 Hz
wavelength = 330/300=1.1 m
wavelength = 330/8000 = 0.04125m
note : i have taken speed of sound as 330 m/s you can take any value given in between 330m/s to 340m/s
Answer
given,
speed of car = 60 km/hr
= 60 x 0.278 m/s
= 16.68 m/s
radius of the tire = 25 cm = 0.25 m
time taken to stop = 6 s
average acceleration = ?


average acceleration= 
= 
= 11.12 rad/s²
correct answer option D
b) length of sea saw = 10 m
mass of jack = 100 Kg
mass of Jill = 60 Kg
Let y be the distance from the Jack. To balance the seesaw moment on both side should balance each other about fulcrum
now,
100 x y = 5 x 60
y = 3 m
the correct answer is option B