a) 2.75 s
The vertical position of the ball at time t is given by the equation
where
h = 4 m is the initial height of the ball
u = 12 m/s is the initial velocity of the ball (upward)
g = 9.8 m/s^2 is the acceleration of gravity (downward)
We can find the time t at which the ball reaches the ground by substituting y=0 into the equation:
This is a second-order equation. By solving it for t, we find:
t = -0.30 s
t = 2.75 s
The first solution is negative, so we discard it; the second solution, t = 2.75 s, is the one we are looking for.
b) -15.0 m/s (downward)
The final velocity of the ball can be calculated by using the equation:
where
u = 12 m/s is the initial (upward) velocity
g = 9.8 m/s^2 is the acceleration of gravity (downward)
t is the time
By subsisuting t = 2.75 s, we find the velocity of the ball as it reaches the ground:
And the negative sign means the direction is downward.
Answer:
So frigid temps I think .
Explanation:
The neritic zone is a shallow zone of water. It is sunlit and it receives ample solar insolation all year round. The salinity of this zone is very stable. This makes for organism to thrive. The neritic zone is home to diverse aquatic life.
What are the options so that I can help.
Resistance-1 = (voltage-1) / (current-1) =
(12 V) / (0.185 A) = 64.9 ohms .
Resistance-2 = (voltage-2) / (current-2) =
(90 V ) / (1.25 A) = 72 ohms .
The resistance changed between situation-1 and situation-2 .
How did that happen ?
Power = (voltage) x (current)
Power-1 = (12) x (0.185) = 2.22 watts
Power-2 = (90) x (1.25) = 112.5 watts
The poor resistor dissipated 51 times as much power during
the second trial. It got all heated up, and its resistance went
through the roof.
Carbon resistors behave nicely and reliably, until you try to
toast bread or light up your bedroom with them.
Answer:
The cannon ball was not able to hit the target because the target is located at a height of 50 m whereas the cannon ball was only above to get to a height of 20 m.
Explanation:
From the question given above, the following data were obtained:
Height to which the target is located = 50 m
Initial velocity (u) = 20 m/s
To know whether or not the cannon ball is able to hit the target, we shall determine the maximum height to which the cannon ball attained. This can be obtained as follow:
Initial velocity (u) = 20 m/s
Final velocity (v) = 0 (at maximum height)
Acceleration due to gravity (g) = 10 m/s²
Maximum height (h) =?
v² = u² – 2gh (since the ball is going against gravity)
0² = 20² – (2 × 10 × h)
0 = 400 – 20h
Collect like terms
0 – 400 = – 20h
– 400 = – 20h
Divide both side by – 20
h = – 400 / – 20
h = 20 m
Thus, the the maximum height to which the cannon ball attained is 20 m.
From the calculations made above, we can conclude that the cannon ball was not able to hit the target because the target is located at a height of 50 m whereas the cannon ball was only above to get to a height of 20 m.
