Answer:
20000 pounds
Explanation:
Generally 1 gallon of fuel burnt gives of 20 pounds of CO₂
Difference in the gallons of fuel burnt
The 20 mpg car burns 1000 gallons of fuel more than the 30 mpg car
The amount of CO₂ would be
The fewer pounds that the 30 mpg car would release is 20000 pounds
Answer:
The actual work output is 1,125 kilojoules.
Explanation:
Energy efficiency is defined as the efficient use of energy. An appliance, process, or facility is energy efficient when it consumes less than the average amount of energy to perform an activity. Then, energy efficiency is the ratio between the amount of energy used in an activity and the amount expected to be carried out.
Efficiency is calculated as:
efficiency = output / input
Where output is the amount of mechanical work (in watts) or energy consumed by the process (in joules), and input (input) is the amount of work or energy that is used as input to carry out the process.
In this case:
- Efficiency always has a value between 0 and 1. In this case, efficiency=0.15
- output=?
- input= 7500 kilojoules
Replacing:
0.15=output/7500 kilojoules
Solving:
Output=0.15* 7500 kilojoules
output=1,125 kilojoules
<u><em>The actual work output is 1,125 kilojoules.</em></u>
Answer:
6.25 m/s
Explanation:
Given parameters
Initial mark = 65
Final mark = 15
time taken = 8s
Unknown:
Velocity of the runner = ?
Solution:
Velocity is the displacement divided by time;
Velocity = 
Displacement = Initial mark - final mark = 65 - 15 = 50m
Now, insert the parameters and solve;
Velocity = 
= 6.25m/s
Answer:
a) It will be easier to apply all her force as far as possible from the axle
b) There is a net torque applied
Explanation:
a) Applying a larger force far away from the axle of the door produces a larger force on the torque than pushing it near the axle. This is because Increasing the lever arm between the axle and the point at which you push the door increases the torque on the door
b)The door is turning faster and faster because you are exerting a torque on it and its undergoing angular acceleration. There is a net torque which is the addition of the torque applied on the opposite sides of the door
