Answer:
2.5 sec
Step-by-step explanation:
Height of wall = 2.5 m
initial speed of ball = 14 m/s
height from which ball is kicked = 0.4 m
we calculate the speed of the ball at the height that matches the wall first
height that matches wall = 2.5 - 0.4 = 2.1 m
using = + 2as
where a = acceleration due to gravity = -9.81 m/s^2 (negative in upwards movement)
= + 2(-9.81 x 2.1)
= 196 - 41.202
= 154.8
v = = 12.44 m/s
this is the velocity of the ball at exactly the point where the wall ends.
At the maximum height, the speed of the ball becomes zero
therefore,
u = 12.44 m/s
v = 0 m/s
a = -9.81 m/s^2
t = ?
using V = U + at
0 = 12.44 - 9.81t
-12.44 = -9.81
t = -12.44/-9.81
t = 1.27 s
the maximum height the ball reaches will be gotten with
= + 2as
a = -9.81 m/s^2
0 = + 2(-9.81s)
0 = 196 - 19.62s
s = -196/-19.62 = 9.99 m. This the maximum height reached by the ball.
height from maximum height to height of ball = 9.99 - 2.5 = 7.49 m
we calculate for the time taken for the ball to travel down this height
a = 9.81 m/s^2 (positive in downwards movement)
u = 0
s = 7.49 m
using s = ut + a
7.49 = (0 x t) + (9.81 x )
7.49 = 0 + 4.9
= 7.49/4.9 = 1.53
t = = 1.23 sec
Total time spent above wall = 1.27 s + 1.23 s = 2.5 sec
Answer:
area after 8 years is 2156km²
Step-by-step explanation:
Area of forest=4900 km²
decrease in area in 1 year=4900km² × 7%
decrease in area in 1 year= 343km²
decrease area in 8 years=343km² × 8
=2744km²
Remaining area= (4900-2744)km²
=2156km²
Note:If you have any question about it please ask.
Answer: ∠R = 137°
<u>Step-by-step explanation:</u>
The opposite angles of a quadrilateral are supplementary (equal to 180°).
Since ∠P and ∠R are opposite angles, their sum is 180°
∠P + ∠R = 180°
y + 3y + 8 = 180
4y + 8 = 180
4y = 172
y = 43
∠R = 3y + 8
= 3(43) + 8
= 129 + 8
= 137
Answer:
All real numbers are solutions!
Step-by-step explanation:
Let's solve your equation step-by-step.
5x+4=9+5(x−1)
Step 1: Simplify both sides of the equation.
5x+4=9+5(x−1)
5x+4=9+(5)(x)+(5)(−1)(Distribute)
5x+4=9+5x+−5
5x+4=(5x)+(9+−5)(Combine Like Terms)
5x+4=5x+4
5x+4=5x+4
Step 2: Subtract 5x from both sides.
5x+4−5x=5x+4−5x
4=4
Step 3: Subtract 4 from both sides.
4−4=4−4
0=0