Answer:
The initial velocity of the ball is 28.714 m/s
Explanation:
Given;
time of flight of the ball, t = 2.93 s
acceleration due to gravity, g = 9.8 m/s²
initial velocity of the ball, u = ?
The initial velocity of the ball is given by;
v = u + (-g)t
where;
v is the final speed of the ball at the given time, = 0
g is negative because of upward motion
0 = u -gt
u = gt
u = (9.8 x 2.93)
u = 28.714 m/s
Therefore, the initial velocity of the ball is 28.714 m/s
Answer:
It will increase
Explanation:
The kinetic energy is the energy possessed by a moving object and is given by:
KE = 
where m = mass of the object and v = velocity of the object.
It does means that the more the mass of an object in motion, the more the kinetic energy of the object if there are no opposing force such as friction. Also, the more the kinetic energy of the object, the more the speed of that object.
<em>Hence, as the weight of the cart increases by addition of groceries, the kinetic energy increases and the speed also increases as it moves along the frictionless surface.</em>
Answer:
233.1 miles per hours
Explanation:
Speed: This is defined as the ratio of distance to time. The S.I unit of speed is m/s. speed is a vector quantity because it can only be represented by magnitude only. Mathematically, speed can be expressed as,
S = d/t ....................... Equation 1
Where S = speed of the runner, d = distance covered, t = time.
Given: d = 100 meter , t = 9.580 seconds
Conversion:
If, 1 meter = 0.00062 miles
Then, 100 meters = (0.00062×100) miles = 0.62 miles.
Also
If, 3600 s = 1 h
Then, 9.580 s = (1×9.580)/3600 = 0.00266 hours.
Substitute into equation 1
S = 0.62/0.00266
S = 233.1 miles per hours.
Hence the runner speed is 233.1 miles per hours
By definition, a region of space that contains no matter at all is a vacuum.
