Answer:
7 m/s^2
Explanation:
Given that the jet is traveling 37.6 m/s when the pilot receives the message.
And it takes the pilot 5.37 s to bring the plane to a halt.
Acceleration of the plane can be calculated by using first equation of motion
V = U - at
Since the plane is going to stop, the final velocity V = zero.
And the acceleration will be negative
Substitute all the parameters into the formula
0 = 37.6 - 5.37a
5.37a = 37.6
Make a the subject of formula
a = 37.6 / 5.37
a = 7.0 m/s^2
Therefore, the acceleration of the plane to bring the plane to a halt is 7 m/s^2
Answer:
W = 34.64 ft-lbs
Explanation:
given,
Horizontal force = 4 lb
distance of push, d = 10 ft
angle of ramp, θ = 30°
Work done on the box = ?
We know,
W = F.d cos θ
W = 4 x 10 x cos 30°
W = 40 x 0.8660
W = 34.64 ft-lbs
Hence, work done on the box is equal to W = 34.64 ft-lbs
Answer:
The time of flight of the ball is 1.06 seconds.
Explanation:
Given 
Also, 
Let us say the velocity in the x-direction is 
and in the y-direction is 
. And acceleration in the x-direction is 
and in the y-direction is 
.
Also, 
is distance covered in x and y direction respectively. And 
is the time taken by the ball to hit the backboard.
We can write 
. Where 
is velocity of ball.
Now,
Also,
.
Plugging this value in
So, the time of flight of the ball is 1.06 seconds.
Democritus was the one who did not have experimental evidence to support his theory of the atom.
Answer: Option 4
<u>Explanation:
</u>
The discovery of atoms were first stated by Democritus but due to the absence of any experimental proof, his statement was not noted as significant at that time.
After this, Dalton made the specific assumptions formulating some postulates for the atomic theory with proof. Then the cathode rays tube experiments performed by Thomson lead to the formation of plum pudding models of atom.
This is followed by Rutherford’s gold foil experiment discovering the presence of nucleus inside the atoms. So, Democritus first stated but due to absence of experimental evidences, his theory of atoms were not supported at that time.
