The goalkeeper at his goal cannot kick a soccer ball into the opponent’s goal without the ball touching the ground
Explanation:
Consider the vertical motion of ball,
We have equation of motion v = u + at
Initial velocity, u = u sin θ
Final velocity, v = 0 m/s
Acceleration = -g
Substituting
v = u + at
0 = u sin θ - g t
This is the time of flight.
Consider the horizontal motion of ball,
Initial velocity, u = u cos θ
Acceleration, a =0 m/s²
Time,
Substituting
s = ut + 0.5 at²
This is the range.
In this problem
u = 30 m/s
g = 9.81 m/s²
θ = 45° - For maximum range
Substituting
Maximum horizontal distance traveled by ball without touching ground is 45.87 m, which is less than 95 m.
So the goalkeeper at his goal cannot kick a soccer ball into the opponent’s goal without the ball touching the ground
Answer:
#see solution for details
Explanation:
-Uncertainty refers to an estimate of the amount by which a result may differ from this value,
-Precision refers to how closely repeated measurements agree with each other.
-Accuracy refers to how closely a measured value agrees with the correct value.
-The number of significant figures is the number of digits believed to be correct by the person doing the measuring. Therefore, choosing the correct number of significant figures reduces the deviation from the point of accuracy/uncertainty or precision and thereby reducing margin of error in the ensuing calculations.
politics. Famous possible eg is of Werner Heisenberg in WW2. He delayed German attempt to build a nuclear bomb. US did build one ... hiroshima and nagasaki.
debbie may have got skilfully lucky by trial and error
Answer:
7.1 m/s
Explanation:
First, find the time it takes for the fish to reach the water.
Given in the y direction:
Δy = 6.1 m
v₀ = 0 m/s
a = 9.8 m/s²
Find: t
Δy = v₀ t + ½ at²
6.1 m = (0 m/s) t + ½ (9.8 m/s²) t²
t = 1.12 s
Next, find the velocity needed to travel 7.9 m in that time.
Given in the x direction:
Δx = 7.9 m
a = 0 m/s²
t = 1.12 s
Find: v₀
Δx = v₀ t + ½ at²
7.9 m = v₀ (1.12 s) + ½ (0 m/s²) (1.12 s)²
v₀ = 7.1 m/s
Answer:
d = 19.796m
Explanation:
Since the ball is in the air for 4.02 seconds, the ball should reach the maximum point from the ground in half the total time, therefore, t=2.01s to reach maximum height. At the maximum height, the velocity in the y-direction is 0.
So we know t=2.01, vi=0, g=a=9.8m/s and we are solving for d.
Next, you look for a kinematic equation that has these parameters and the one you should choose is:
Now by substituting values in, we get
d = 19.796m
