Answer:
1)

2)

Explanation:
<u>Projectile Motion</u>
When an object is launched near the Earth's surface forming an angle
with the horizontal plane, it describes a well-known path called a parabola. The only force acting (neglecting the effects of the wind) is the gravity, which acts on the vertical axis.
The heigh of an object can be computed as

Where
is the initial height above the ground level,
is the vertical component of the initial velocity and t is the time
The y-component of the speed is

1) We'll find the vertical component of the initial speed since we have not enough data to compute the magnitude of 
The object will reach the maximum height when
. It allows us to compute the time to reach that point

Solving for 

Thus, the maximum heigh is

We know this value is 8 meters

Solving for 

Replacing the known values


2) We know at t=1.505 sec the ball is above Julie's head, we can compute




Distance = speed * time, then time = distance / speed.
time = 50 / 0.4 = 125 s
Answer:
The time to boil the water is 877 s
Explanation:
The first thing we must do is calculate the external resistance (R) of the circuit, from the description we notice that it is a series circuit, by which the resistors are added
V = i (r + R)
We replace we calculate
r + R = V / i
R = v / i - r
R = 10/12 -0.04
R = 0.793 Ω
We calculate the power supplied
P = V i = I² R
P = 12² 0.793
P = 114 W
This is the power dissipated in the external resistance
We use the relationship, that power is work per unit of time and that work is the variation of energy
P = E / t
t = E / P
t = 100 10³/114
t = 877 s
The time to boil the water is 877 s
Answer:
The distance and height of the object is 6 m and 2 m.
The image is virtual and upright.
Explanation:
Given that,
Focal length = 0.25 m
Length of image = 0.080 m
Image distance = 0.24 m
We need to calculate the distance of the object
Using formula of lens

Put the value into the formula




We need to calculate the magnification
Using formula of magnification

Put the value into the formula


We need to calculate the height of the object
Using formula of magnification



A convex mirror produce a virtual and upright image behind the mirror.
Hence, The distance and height of the object is 6 m and 2 m.
The image is virtual and upright.