Answer:
a) t=1s
y = 10.1m
v=5.2m/s
b) t=1.5s
y =11.475 m
v=0.3m/s
c) t=2s
y =10.4 m
v=-4.6m/s (The minus sign (-) indicates that the ball is already going down)
Explanation:
Conceptual analysis
We apply the free fall formula for position (y) and speed (v) at any time (t).
As gravity opposes movement the sign in the equations is negative.:
y = vi*t - ½ g*t2 Equation 1
v=vit-g*t Equation 2
y: The vertical distance the ball moves at time t
vi: Initial speed
g= acceleration due to gravity
v= Speed the ball moves at time t
Known information
We know the following data:
Vi=15 m / s

t=1s ,1.5s,2s
Development of problem
We replace t in the equations (1) and (2)
a) t=1s
=15-4.9=10.1m
v=15-9.8*1 =15-9.8 =5.2m/s
b) t=1.5s
=22.5-11.025=11.475 m
v=15-9.8*1.5 =15-14.7=0.3m/s
c) t=2s
= 30-19.6=10.4 m
v=15-9.8*2 =15-19.6=-4.6m/s (The minus sign (-) indicates that the ball is already going down)
Equal to 50
law of reflection: angle of incidence equals angle of reflection
Answer: Current, resistance and voltage are the quantities which are related by Ohm's law.
Explanation:
A law which states that electric current is directly proportional to voltage and inversely proportional to resistance is called Ohm's law.
Mathematically, it is represented as follows.

where,
I = current
V = voltage
R = resistance
This means that the quantities related by Ohm's law include current, voltage and resistance.
Thus, we can conclude that current, resistance and voltage are the quantities which are related by Ohm's law.
Answer:
20 m/s
Explanation:
The speed of a wave is given by:

where
is the wavelength
f is the frequency
v is the speed
For the wave in this problem,
f = 10 Hz is the frequency
is the wavelength
So the speed is

Decay of Schizomycetes waste present in waste water leads to unpleasant smell.
These microorganisms, known as iron and sulfur bacteria, cause hydrogen sulfide to be found in water supplies. They include crenothrix and beggiatoa. Most often found in groundwater supplies, they produce an offensive odor of decaying matter. (I'm not sure)