Answer:
(a) 
(b) 142
(c) 
(d) 96.8 mph
(e) 0.426 s
(f) 0.061 rad
Explanation:
Velocity is a time-derivative of position.
(a) 

(b) Since
is independent of
, it follows it was constant throughout. Hence, at any point or time, the horizontal velocity is 142.
(c) 

(d) When it passes the home plate, the ball has travelled 60.5 ft (from the question). This is horizontal, so it is equivalent to
.

.
In this time, the vertical velocity,
is

The speed of the ball at thus point is
ft/s
To convert this to mph, we multiply the factor 3600/5280

(e) The time has been determined from (d) above.

(f) This angle is given by

(Note here we are considering the acute angle so we ignore the negative sign)
In radians, this is

Answer:
0.932 m/h
Explanation:
Parameters given:
Distance walked by couple, D = 1.5 km
Time spent in walking, t = 60 min
To solve this we simply apply the formula for average peed:
Average Speed = total distance / total time taken
The question asks specifically to put the answer in miles per hour (m/h), hence, we need to convert the distance to miles and the time to hours:
Distance in miles:
1 km = 0.622 miles
1.5 km = 1.5 * 0.622 = 0.932 miles
Time in hours = 60 / 60 = 1 hour
Hence, the speed is:
Speed = 0.932 / 1 = 0.932 m/h
The average speed of the couple is 0.932 m/h
Answer: Samantha has the largest centripetal acceleration of 2.4 m/s^2. Maria has only 1.69 m/s^2.
Explanation:
Answer:
Final velocity of electron,
Explanation:
It is given that,
Electric field, E = 1.55 N/C
Initial velocity at point A, 
We need to find the speed of the electron when it reaches point B which is a distance of 0.395 m east of point A. It can be calculated using third equation of motion as :
........(1)
a is the acceleration, 
We know that electric force, F = qE

Use above equation in equation (1) as:


v = 647302.09 m/s
or

So, the final velocity of the electron when it reaches point B is
. Hence, this is the required solution.