Answer:
A 2 d vector model
The acceleration function is -9.8 m/s2 which is gravity
Initial velocity on the Y axis is 0, on the X axis is 12 m/s
Inital position is 20 mts above the ground.
It takes the water 1.01 seconds to reach the other building.
THe distace from one building to the other is 12.11 meters.
Explanation:
In order to solve this you just need to carefully read the problem and the data you are given, and use the formula for height in free fall:

So first the data, we know that the water is coming out at a height of 20 meters since the building is 19 meters tall and the fireman is holding the firehose 1 meter above it, and the water is hitting the second building at a height of 15 meters, that means that the water is travelin -5meters.
Gravity as it doesn´t say otherwise would be 9.8m/s2 since that is gravity on earth, and water is leaving the firehose at 12m/s horizontally.
We can calculate the time by using the height formula fro free fall:

So it takes 1.009 seconds for the water to frop from 20 to 15 meters, as the horizontal velocity remains the same we just multiply it by the time and we get the horizontal distance between the two buildings and that would be:
12.11 meters.
Answer:
The average velocity is 40km/h.
Explanation:
The average velocity is
, where
is the distance traveled and
the time elapsed.
The distance traveled is clearly 80km since it's all done in the same direction, we only need to know the time elapsed. For this we calculate the time elapsed on the first part, and add it to the time elapsed on the second part using always the formula
, where v is the velocity on each part, which is constant.
The time elapsed for the first part is
, and the time elapsed for the second part is
, giving us a total time of
=2h.
Finally, we can calculate the average velocity:
.
Answer:
acc to formula= F= G m1m2/rsq
mass of Uranus= F×r sq/G×m
M=3.00×10^25×761.4×761.4×10^6/6.67×10^ -11×3.01×10^21
=3×10^25-8×7614×7614/667×301×10^-2-11+21-2
=173918988×10^11/200767
=866×10^11(approx)
Answer:
Explanation:
Given that,
Gas central heating was used for 5days
At a rate of 102kWh of energy
Then, 1 kWh = 7p
So,
The total time is 5days
t = 5days
1 day = 24hours
Then, t = 5days = 5 × 24 = 120hours
Given 102kWh, then, they consumers 102 kW in one hour, then, for the 120hours,
The total energy used is 102 × 24
Then, total energy = 2448 kWh
So, 1 kWh = 7p,
Then, 2448 kWh = 7 × 2448
2448 kWh = 17,136 p.
So, the cost of the using central heat is 17,136 p