<em>Answers:</em>
<em>1. The hot soup will loose the heat and the ice water will gain the heat</em>
- If two jars are insulated inside the insulated box, the heat may not be transferred to outside of the box.
- According to II law of thermodynamics, Heat always flow from high temperature body to low temperature body, with out aid of external energy.
<em>So, from two points, it is concluded that The hot soup will lose heat and the ice water will gain the heat until they reach the thermodynamic equilibrium.</em>
<em>2. The particles in gases are farther apart and move faster </em>
- Particles in the gases are loosely packed (greater distance between particles compared to solids and liquids) and particles collide less often.
<em>Therefore conduction is weak in gases compared to solids and liquids.</em>
<em>3. Heat and milk by conduction; popping popcorn by radiation.</em>
- The heat can transfer from pot to the milk by conduction because they are in contact at boundaries, similarly the pot and the stove are in contact <em>so the conduction transfers heat from pot to the milk. </em>
- In microwave oven there is no direct contact (<em>no conduction</em>) of heat and popcorn, also there is no molecular momentum transfer <em>(means of no convection).</em>
<em>So obviously the heat transfer by radiation occurs in a microwave oven.</em>
Answer:
wo = 18.75 rev / s
Explanation:
This is an exercise in endowment kinematics, it indicates that the final angular velocity is w_f = 109 rad / s, the time to reach this velocity is t = 1.87 s and the deceleration a = 4.7 rad / s²
w_f = w₀ - a t
w₀ = w_f + a t
w₀ = 109 + 4.7 1.87
w₀ = 117.8 rad / s
let's reduce to revolutions / s
w₀ = 117.8 rad / s (1 rev / 2pi rad)
w₀ = 18.75 rev / s
Answer:
Explanation:
for baseball
(a) Let the mass of the baseball is m.
radius of baseball is r.
Total kinetic energy of the baseball, T = rotational kinetic energy + translational kinetic energy
T = 0.5 Iω² + 0.5 mv²
Where, I be the moment of inertia and ω be the angular speed.
ω = v/r
T = 0.5 x 2/3 mr² x v²/r² + 0.5 mv²
T = 0.83 mv²
According to the conservation of energy, the total kinetic energy at the bottom is equal to the total potential energy at the top.
m g h = 0.83 mv²
where, h be the height of the top of the hill.
9.8 x h = 0.83 x 6.8 x 6.8
h = 3.93 m
(b) Let the velocity of juice can is v'.
moment of inertia of the juice can = 1/2mr²
So, total kinetic energy
T = 0.5 x I x ω² + 0.5 mv²
T = 0.5 x 0.5 x m x r² x v²/r² + 0.5 mv²
m g h = 0.75 mv²
9.8 x 3.93 = 0.75 v²
v = 7.2 m/s
Answer:
12.4 m/s²
Explanation:
L = length of the simple pendulum = 53 cm = 0.53 m
n = Number of full swing cycles = 99.0
t = Total time taken = 128 s
T = Time period of the pendulum
g = magnitude of gravitational acceleration on the planet
Time period of the pendulum is given as
T = 1.3 sec
Time period of the pendulum is also given as
g = 12.4 m/s²