Answer: 3.1107grams of fat.
Explanation:The speed to cover 800 km in 20 hours will be 40km/hr, Because
Speed =Distance/Time.
This is equal to 72,000 seconds. At a power consumption of 1.7 W, the bird will consume (1.7 X 72,000) =122,400 J of energy.
A gram of fat contains about (9.4 Calories X 4186 J/Calorie) ,=39348 joules of energy, the bird will need (122,400 / 39,348) = 3.1107 grams of fat.
Answer:
Part a)
Part b)
Ball thrown downwards =
Ball thrown upwards =
Part c)
Explanation:
Part a)
Since both the balls are projected with same speed in opposite directions
So here the time difference is the time for which the ball projected upward will move up and come back at the same point of projection
Afterwards the motion will be same as the first ball which is projected downwards
so here the time difference is given as
Part b)
Since the displacement in y direction for two balls is same as well as the the initial speed is also same so final speed is also same for both the balls
so it is given as
Part c)
Relative speed of two balls is given as
now the distance between two balls in 0.8 s is given as
Answer:a.They all travel the same distance.
B. Car F
Explanation:
A. For the three cars, we have that
ƒ = μN and since
N = F(g) = mg,
therefore ƒ = μmg.
Considering Inertia as a property of matter which increases with linearly. The more massive a car is, the more inertia carrying it forward, but also the more friction required in trying to stop it, so the two will cancel out and all three cars will stop at same distance
B.For the three cars, we have that,
w = Fd.
The force acting on the cars as they move forward is friction,
therefore w = ƒd. Since ƒ = μN and N = F(g) = mg, then,
ƒ = μmg.
Combining friction equation with the work equation gives us
w = μmgd. As μ, g, and d will be constant between equations, the greatest work done by friction will come from the car with the greatest mass.
It is an real machine because if efficiency is below100% it is real machine but if efficiency is 100% it is an ideal machine