well in order to calculate the speed of the object at the start point you need to know:
# mass/weight of the object
# the air resistance # the angle
# the form of the object
If speed does not change then the object is moving with constant speed. when object moves in a circle its speed does not remains constant. Speed of object remains constant only if it moves along linear path.
The speed of an object at any instant in time is its instantaneous speed.
When a moving object is pushed in the direction of its motion the speed of the object increases
The object remains in constant, uniform motion. That means its speed and direction of motion don't change. Note that its speed may or may not be zero.
the object's 'velocity'
whyh does the sped decreases when an object is thrown vertically up
an object thrown into the air will slow down as it ascends higher into the air until it stops ascending and the speed of the object increases as it falls until it reaches its terminal velocity in air. As an object passes through air, it encounters air resistance which slows down an object moving freely through air. An object will be moving at a slower speed when it hits the ground than it did when it was thrown into the air due to this air resistance.
Yes. Acceleration is independent of speed. A perfect example of an object with zero speed but nonzero acceleration is an object at the apex of being thrown upward. The entire time it is in the air it is accelerating downward. At its maximum height its speed is zero.
No. Regardless of its initial speed, the object still experiences downward acceleration at the rate of 'G'.
Whether the object is dropped, thrown downwards, thrown upwards, or thrown horizontally, its downward acceleration is the same 9.8 meters per second2. If it's thrown downwards, however, its speed at any instant is greater than the speed at the same instant would be if it had only been dropped, since it has some speed before the acceleration begins.
If thrown horizontal from same height the faster object will travel farther horizontally, but time to fall is the same. If thrown straight up, the faster object will take longer to fall
Radar was first used to measure the speed of a moving object in 1935. By 1938, they were used to measure the speed of a fastball thrown by Bob Feller.
it would be slower
I do not know what a "song shoot" is, but I will attempt to generically answer the second half of the question in regards to a brick compared to anything else. If a brick is thrown/fired/shot, it will have a different aerodynamic drag that anything that doesn't have the same shape. If a brick thrown/fired/shot with the same force as a lighter object, the brick will have a lower speed. If the speed of the two objects are the same, the brick required more force than the lighter object. If a brick thrown/fired/shot at the same angle as another object, the arch will be the same, as acceleration is independant of mass.
The difference between an object's speed and an object's velocity is that the object's speed is how fast it is going, and the object's velocity is how many units of speed the object has traveled.
WHAT THE SPEED OF STATIONARY OBJECT?
Speed of an object at one instant of time is the object's instantaneous speed.(Not velocity.)