Answer:
1/2 m v^2 + 1/2 I ω^2 = m g h conservation of energy
I = 2/5 m R^2 inertia of solid sphere
1/2 m v^2 + 1/5 m ω^2 R^2 = m g h
1/2 v^2 + 1/5 v^2 = g h
v^2 = 10 g h / 7 = 1.43 * 9.80 * 19 m^2/s^2 = 266 m^2/s^2
v = 16.3 m/s
v = R ω
ω = 16.3 / .6 = 27.2 / sec
Answer:
143.352 watt.
Explanation:
So, in the question above we are given the following parameters or data or information that is going to assist us in answering the question above efficiently. The parameters are:
"A 1.8 m wide by 1.0 m tall by 0.65m deep home freezer is insulated with 5.0cm thick Styrofoam insulation"
The inside temperature of the freezer = -20°C.
Thickness = 5.0cm = 5.0 × 10^-2 m.
Step one: Calculate the surface area of the freezer. That can be done by using the formula below:
Area = 2[ ( Length × breadth) + (breadth × height) + (length × height) ].
Area = 2[ (1.8 × 0.65) + (0.65 × 1.0) + (1.8 × 1.0)].
Area = 7.24 m^2.
Step two: Calculate the rate of heat transfer by using the formula below;
Rate of heat transfer =[ thermal conductivity × Area (T1 - T2) ]/ thickness.
Rate of heat transfer = 0.022 × 7.24(25+20)/5.0 × 10^-2 = 143.352 watt.
Answer:
Explanation:
The forces acting on a conductor carrying current placed in a magnetic field is analysed using the Fleming's left hand rule.
The rule states that "If the fire finger, the middle finger and the thumb are held mutually perpendicular to one another in a magnetic field, the fore finger acts in the direction of the magnetic field, the middle finger acts on the direction of the current while the thumb acts in the direction of the force.
Based on the rule, it can be inferred this current carrying wire placed in the magnetic field acts perpendicular to the magnetic field and force acting on the wire.
Answer: Option B
The wavelength for a radio wave with a frequency of 2 × 10⁴ Hz is
1.5 × 10⁴ m.
Explanation:
Wavelength is the measure of distance between two successive crests or troughs in a standing wave. Also wavelength can be measured as the ratio of velocity of light to frequency. It is like this because wavelength is inversely proportional to the frequency.
As c = 3 × 10⁸ m/s and the frequency is 2 × 10⁴ Hz, then the wavelength will be
So, the wavelength for a radio wave with a frequency of 2 × 10⁴ Hz is
1.5 × 10⁴ m.
Answer:
they are the source of energy for primary consumers... they also produce oxygen and sugar
