To get this we need to know how long he was traveling. To know that we need to solve for the time it took for him to hit the ground. This is given by the vertical height he started at and the equation of motion for falling objects. The position function is
Y= -(9.8/2)t^2 + 50 = 0
t=3.19s
That's how long he's in the air. When he hits the ground he stops moving forward so this is also the amount of time he was moving at 100m/s horizontally. Now use speed distance relationship
X=vt
And solve for v
100m/3.19s = 31.35m/s
Answer:
45 J
Explanation:
Assuming the level at which the ball is thrown upwards is the ground level,
We can use the equations of motion to obtain the maximum height covered by the ball and then calculate the potential energy
u = initial velocity of the ball = 3 m/s
h = y = vertical distance covered by the ball = ?
v = final velocity of the ball at the maximum height = 0 m/s
g = acceleration due to gravity = -9.8 m/s²
v² = u² + 2ay
0 = 3² + 2(-9.8)(y)
19.6y = 9
y = (9/19.6)
y = 0.459 m
The potential energy the ball will have at the top of its motion = mgh
mgh = (10)(9.8)(0.459) = 45 J
Hope this Helps!!!
Answer:
B- He is correct. Evaporation is a physical change, but dissolving salt in water is a chemical change. The change in mass is evidence that a chemical change occurred.
Explanation: Dissolving Salt in water is a Chemical Change, Because the Salt arrangement is different in solid state than dissolved in water. As we can see in the image below, once the Salt is dissolved, it is separated into its ions, Na+ and Cl- Now, The evaporation process is a physical change, because the water doesn´t change its configuration H20 and it only changes its form, as we can see in the image below.
Answer:
45°.
It is a property of the parabolas.. When the angle between a parabola and the x-axis is 45° the range is maximum.
