The difference between speed and velocity is that the speed is a scalar quantity which means that you can say that this object has a speed of x m/s but you don't have to define its direction
while the velocity is a vector quantity which means that you have to express the velocity by which it moves in x,y and z directions and its norm is the speed
Answer:
Impulse will be 12 kgm/sec
So option (b) will be correct option
Explanation:
We have given mass of the baseball m = 0.15 kg
Ball speed before hit 
Ball speed after hitting
( negative direction due to opposite direction )
We have to find the impulse
We know that impulse is equal; to the change in momentum
So change in momentum = 
So option (b) will be correct option
That's the only way you can get consistent and accurate results.
The principle of resistance training that suggests that muscles should be gradually required to do more than they are used to doing is D. OVERLOAD.
The principle of overload states that a greater than normal stress or load on the body is required for training adaptation to take place.
Overload refers to the amount of load or resistance, providing a greater stress, or load, on the body than it is normally accustomed to in order to increase fitness.
Answer: 0.8 m
Explanation:
Velocity of throw = 4m/s
Maximum Height attained(h) =?
Downward acceleration experienced = 10m/s^2
Using the relation:
v^2 = u^2 + 2aS
v = final Velocity = 0 (at maximum height)
u = Initial Velocity = 4
a = g downward acceleration = - 10
0 = 4^2 + 2(-10)(S)
0 = 16 - 20S
20S = 16
S = 16 / 20
S = 0.8m
Maximum Height attained = 0.8m