Answer:
Force exerted = 25.41 kN
Explanation:
We have equation of motion
v² = u²+2as
u = 345 m/s, s = 8.9 cm = 0.089 m, v = 0 m/s
0² = 345²+2 x a x 0.089
a = -668679.78 m/s²
Force exerted = Mass x Acceleration
Mass of bullet = 38 g = 0.038 kg
Acceleration = 668679.78 m/s²
Force exerted = 25409.83 N = 25.41 kN
Answer:
When the ejected air is moving in the downward direction then the thrust force acts in the upward direction, due to reversal thrust, the jets can take off vertically without needing a runway this way.
Explanation:
Newton’s third law motion states that for every action there will be an equal and opposite reaction.
Thrust reversal is also known as reverse thrust. It acts opposite to the motion of the aircraft by providing the deceleration.
Commercial aircraft moves the ejected air in the forward direction means that the thrust will acts opposite to the motion of the aircraft that is backward direction due to thrust reversal. This thrust force might be used to decelerate the craft.
Uses of thrust reversal in practice:
When the ejected air is moving forward direction then the thrust force moving backward direction due to reversal thrust the speed of the craft slows down.
When the ejected air is moving in the downward direction then the thrust force acts in the upward direction, due to reversal thrust, the jets can take off vertically without needing a runway this way.
Answer:
Tangential speed, v = 2.64 m/s
Explanation:
Given that,
Mass of the puck, m = 0.5 kg
Tension acting in the string, T = 3.5 N
Radius of the circular path, r = 1 m
To find,
The tangential speed of the puck.
Solution,
The centripetal force acting in the string is balanced by the tangential speed of the puck. The expression for the centripetal force is given by :
v = 2.64 m/s
Therefore, the tangential speed of the puck is 2.64 m/s.
L=G·d
L=600N·3m=1800J
P=L/Δt=1800J/4s=450W
Answer:
Approximately 
. (Assuming that this table is level, and that the gravitational field strength is 
.
Explanation:
Convert the dimensions of this book to standard units:
.
.
Calculate the surface area of this book:
.
Pressure is the ratio between normal force and the area over which this force is applied.
.
Equivalently:
.
In this question, 
.
It was found that 
(assuming that the entire side of this book is in contact with the table.
Hence:
.
If that the table is level, this normal force would be equal to the weight of this book:
.
Assuming that the gravitational field strength is . The mass of this book would be:
.
