Answer:
T = 0.225 s
Explanation:
The speed of a projectile at the highest point of its motion is the horizontal speed of the projectile. Considering the horizontal motion with negligible air resistance, we can use the following formula:

where,
T = Total time of ball in air = ?
R = Horizontal distance covered = 40 m
= horizontal speed = 9 m/s
Therefore,

<u>T = 0.225 s</u>
An object's momentum is the product of its mass and its velocity:
p = mv
p is its momentum, m is its mass, and v is its velocity.
Given values:
p = -80kg×m/s
m = 8kg
Plug in these values and solve for v:
-80 = 8v
v = -10m/s
Choice D
Answer:
D: The side of Magnet A that's attracted to Magnet B's south pole must be Magnet A's north pole
Explanation:
D: The side of Magnet A that's attracted to Magnet B's south pole must be Magnet A's north pole because
1) opposite poles attract each other
2) similar poles repel each other
3)magnetic lines of force start at the north pole and end at the south pole
Answer:
B) - 5.0 m
Explanation:
B is located on a positive location, 15m from the starting point A. Hence, since E is located a positive distance 10m from A, the difference becomes 10 - 15 = - 5.0 m
Calculate its average speed in meters per second
Answer:
5.77 m/s
Explanation:
Speed= Distance/Time
Distance= 40+ half of 40= 40+20= 60 m
Time= 8.8+1.6=10.4 s
Average speed= 60/10.4=5.769230769 m/s
Approximately, the average speed is 5.77 m/s