Answer:
<em>The speed of the plane after it decelerates is 50 m/s</em>
Explanation:
<u>Motion with Constant Acceleration</u>
When an object gains or losses velocity in time, it acquires acceleration. If this value is constant, we can calculate the final velocity (or speed in scalar terms) as:
Where vf is the final speed, vo is the initial speed, a is the constant acceleration, and t is the time the acceleration is acting.
The plane is originally traveling at vo=80 m/s and it slows down at a constant rate of during t=120 seconds. Note we have added the negative sign to the acceleration because the plane is slowing down, i.e., the acceleration is against the speed.
Thus, the final speed is:
The speed of the plane after it decelerates is 50 m/s
Answer:
76.4m/s
Explanation:
Given parameter:
Time taken = 7.8sec
Unknown:
Speed after it dropped = ?
Solution:
To solve this problem, we use one of the kinematics equation:
V = U + gt
V is the final speed
U is the initial speed = 0m/s
g is the acceleration due to gravity
t is the time taken
V = 0 + 9.8 x 7.8 = 76.4m/s
Answer:
the force will decrease to 3/4 of its original value.
Explanation:
The initial electric force between the two charges is:
where
k is the Coulomb's constant
q is the magnitude of each charge
r is their separation
Later, half of one charge is transferred to the other charge; this means that one charge will have a charge of
while the other charge will be
So, the new force will be
So, the force will decrease to 3/4 of its original value.