First, we convert kcal to joules:
1 kcal = 4.184 kJ
475 kcal = 1987.4 kJ
Now, calculating the change in internal energy:
ΔU = Q + W; where Q is the heat supplied to the system and W is the work done on the system.
ΔU = -500 + 1987.4
ΔU = 1487.4 kJ
Refer to the diagram shown below.
Assume that air resistance is ignored.
Note:
The distance, h, of a falling object with initial vertical velocity of zero at time t is
h = (1/2)gt²
where
g = 9.8 m/s²
The initial vertical velocity of the supplies is 0 m/s.
It the time taken for the supplies to reach the ground is t, then
(50 m) = (1/2)*(9.8 m/s²)*(t s)²
Hence obtain
t² = 50/4.9 = 10.2041
t = 3.1944 s
The horizontal distance traveled at a speed of 100 m/s is
d = (100 m/s)*(3.1944 s) = 319.44 m
Answer: 319.4 m (nearest tenth)
The correct answer would be 1.35m/s sw.
Answer:
2069.76 N
Explanation:
density of wood = 824 kg/m^3
density of water = 1000 kg/m^3
Volume of wood = 1.2 m^3
True weight of wood = volume of wood x density of wood x gravity
True weight of wood = 1.2 x 824 x 9.8 = 9690.24 N
Buoyant force acting on wood = volume of wood x density of water x gravity
Buoyant force acting on wood = 1.2 x 1000 x 9.8 = 11760 N
Tension in the rope = Buoyant force - True weight
tension in rope = 11760 - 9690.24 = 2069.76 N