Answer:
Vi = 32 [m/s]
Explanation:
In order to solve this problem we must use the following the two following kinematics equations.
The negative sign of the second term of the equation means that the velocity decreases, as indicated in the problem.
where:
Vf = final velocity = 8[m/s]
Vi = initial velocity [m/s]
a = acceleration = [m/s^2]
t = time = 5 [s]
Now replacing:
8 = Vi - 5*a
Vi = (8 + 5*a)
As we can see we have two unknowns the initial velocity and the acceleration, so we must use a second kinematics equation.
where:
d = distance = 100[m]
(8^2) = (8 + 5*a)^2 - (2*a*100)
64 = (64 + 80*a + 25*a^2) - 200*a
0 = 80*a - 200*a + 25*a^2
0 = - 120*a + 25*a^2
0 = 25*a(a - 4.8)
therefore:
a = 0 or a = 4.8 [m/s^2]
We choose the value of 4.8 as the acceleration value, since the zero value would not apply.
Returning to the first equation:
8 = Vi - (4.8*5)
Vi = 32 [m/s]
Answer:
<u>Family</u>
1. Definition of a family
A family is a group of people living together in a home related by blood, marriage or adoption.
2. Two function of the family are;
- socialization for the children in the family.
- love and happiness should be in a family for it to be function.
3. Two types of family are;
- Single parent family- this family includes one parent and his or her child, we can say it's an incomplete family.
- nuclear family- this family includes the two parents and their children or child, this family is known as the complete family.
4. Two roles and responsibilities of the parents and children in the home are;
- both parents must and should protect their child or children from harm.
- the children must have respect for the family.
<u>Accident in the Home</u>
1. Definition of accident in the home
accidents in the home are common to persons of all ages, therefore home accidents occurs in one's home that may cause an result an injury of a person
2. Two types of accident in the home
- falls
- minor cuts and wounds
3. The two uses of cereals in cooking
Cereals in cooking are used as thickened agents.
4. complete table
1. minor cuts and wounds
- Causes: these are caused by broken glasses, contact with sharp instruments such as knife, pins and needles.
- Prevention: this can be prevented by keeping the Sharp tools in safe places after used
2. Poisoning
- Causes: poisoning can caused by in a result from children taking tablets for sweets, which can lead to death.
- preventions: you can prevent this by avoiding poisoning from the from the home or you could put it at a safe place that you know the child cannot get it.
<u>Care labels</u>
1. definition of care label
care labels can be defined as a permanent label or we can say a tag, which contains regular instructions that is attached at the back of a cloth.
3. two classification of carbohydrates
- Mono
- poly
Answer: The frequency heard will be f = 275.675Hz
Explanation: When an object emitting sound is moving, it occurs a phenomenon called Doppler shift or Doppler effect. What happens is that the sound gets higher when the moving object comes closer the observer and becomes lower after it passes, This change is due to the quantity of waves that passes through an area in an unit of time.
The formula to calculate the Doppler effect is as follows
f = (
) · f₀
f is the observed frequency;
c is the speed of sound;
Vs is velocity of the source;
f₀ is the emitted frequency of source;
Substituting and calculating,
f = 
· 300
f = 275.675 Hz
Thus, the frequency heard by the police officer is 275.675Hz.
As we know that range of the projectile motion is given by
here we know that range will be same for two different angles
so here we can say the two angle must be complementary angles
so the two angles must be
so it is given that one of the projection angle is 75 degree
so other angle for same range must be 90 - 75 = 15 degree
so other projection angle must be 15 degree
