The quantity that has a magnitude of zero when the ball is at the highest point in its trajectory is
the vertical velocity.
In fact, the motion of the ball consists of two separate motions:
- the horizontal motion, on the x-axis, which is a uniform motion with constant velocity
, where
- the vertical motion, on the y-axis, which is a uniformly accelerated motion with constant acceleration
directed downwards, and with initial velocity
. Due to the presence of the acceleration g on the vertical direction (pointing in the opposite direction of the initial vertical velocity), the vertical velocity of the ball decreases as it goes higher, up to a point where it becomes zero and it reverses its direction: when the vertical velocity becomes zero, the ball has reached its maximum height.
To solve this problem we will apply the concepts related to the kinematic equations of linear motion. From them we will consider speed as the distance traveled per unit of time. Said unit of time will be cleared to find the total time taken to travel the given distance. Later with the calculated average times and distances, we will obtain the average speed.
PART A)
The time taken to travel a distance of 250km with a speed of 95km/h is
Time taken for the lunch is
The time taken travel a distance of 250km with a speed of 55km/h
The total time taken is
The average speed is the ratio of total distance and total time
PART B)
As the displacement is zero the average velocity is zero.
Answer:C
Explanation:
Mass energy of hydrogen fusing into helium
Let there be N number of wires.
Maximum tension a wire can withstand = 100 lb
so, Total tension N wires can withstand = 100 N
now, total tension in N wires = Maximum weight of bucket
100 N = W
so, W = 100N
W is the weight of bucket and 100N is its maximum value.
Answer:
the direction that should be walked by Ricardo to go directly to Jane is 23.52 m, 24° east of south
Explanation:
given information:
Ricardo walks 27.0 m in a direction 60.0 ∘ west of north, thus
A= 27
Ax = 27 sin 60 = - 23.4
Ay = 27 cos 60 = 13.5
Jane walks 16.0 m in a direction 30.0 ∘ south of west, so
B = 16
Bx = 16 cos 30 = -13.9
By = 16 sin 30 = -8
the direction that should be walked by Ricardo to go directly to Jane
R = √A²+B² - (2ABcos60)
= √27²+16² - (2(27)(16)(cos 60))
= 23.52 m
now we can use the sines law to find the angle
tan θ = 
= By - Ay/Bx -Ax
= (-8 - 13.5)/(-13.9 - (-23.4))
θ = 90 - (-8 - 13.5)/(-13.9 - (-23.4))
= 24° east of south
