Answer:
a) It will take you 16.94 min to climb the stairs.
b) The numbers of flights are 123 flights.
Explanation:
a) Let the energy consumption while climbing the stairs be 685 W in kcal/min is given by:
rate of energy consumption = (685 W)×[(0.01433kcal/min)/1 W]
= 9.81605 kcal/min
the time it takes to climb the stairs is given by:
t = E/P
= (166.0 kcal)/(9.8 kcal/min)
= 16.94 min
Therefore, it will take you 16.94 min to climb the stairs.
b) Given t is the time it takes to climb stairs and N is the number of stairs to climb per min, then the number of stairs is:
n = t×N
= (16.94)×(116)
= 1965 stairs
given the number of stairs each flight as N1, then the number of flights is given by:
flights = n/N1
= (1965)/(16)
= 123 flights
Therefore, the numbers of flights are 123 flights.
Answer:
3.9 m/s
Explanation:
We are given that
Mass of car,m=
Initial velocity,u=0
Distance,s=5.9 m
Average friction force,f=
We have to find the speed of the car at the bottom of the driveway.
Net force,
Where 
Acceleration,
v=3.9 m/s
Answer: m∠P ≈ 46,42°
because using the law of sines in ΔPQR
=> sin 75°/ 4 = sin P/3
so ur friend is wrong due to confusion between edges
+) we have: sin 75°/4 = sin P/3
=> sin P = sin 75°/4 . 3 = (3√6 + 3√2)/16
=> m∠P ≈ 46,42°
Explanation:
Answer:
a) the acceleration is -9.8 m/s^2 (gravity's acceleration), the magnitude is 9.8 m/s^2 and the direction is downwards.
The pebble is not decelerating since the magnitude of it's speed is increasing, even if it is on a negative direction.
b) after 0.5 s the pebble is 5.725 meters down. (or -5.725m from it's initial position.)
Explanation:
a) the acceleration is given only by gravity, it's the only force acting on the pebble, the slingshot only gives the pebble an initial speed.
b) To calculate the position we use the equation
y0 + v0·t + ½·g·t² = yf
replacing:
0 + (-9.0m/s) * 0.5s + 1/2 (-9.8)*0.5² = yf
-5.725 = yf
