Answer:
3600N
Explanation:
Given: m = 1200kg, Vo = 0m/s, Vf = 30m/s, Δt = 10s
ΣF = ma
we need to find 'a' first, using the definition of 'a' we get equation:
a = (Vf-Vo)/Δt
a = (30m/s)/10s
a = 3 m/s^2
now substitute into top equation
ΣF = ma
Fengine = (1200kg)(3m/s^2)
Fengine = 3600N
The rms speed can be calculated using the following rule:
rms = sqrt ((3RT) / (M)) where:
R is the gas constant = 8.314 J/mol-K
T is the temperature = 31.5 + 273 = 304.5 degrees kelvin
M is the molar mass = 2*14 = 28 grams = 0.028 kg
Substitute with the givens to get the rms speed as follows:
rms speed = sqrt [(3*8.314*304.5) / (0.028)] = 520.811 m/sec
Check the power source. Your thermostat may just not be connected right or at all. A blown fuse, tripped circuit breaker or dead batteries will prevent the thermostat from turning on your furnace.
Dirty thermostat? That’ll cause issues. Clean up any dust, dirt, spider webs and other debris. Any of these things can coat the inside of the thermostat and interfere with both electrical and mechanical functions of the thermostat. Put this on your get-ready-for-winter cleaning list. Just use a soft, clean brush to clean the inside components gently. Don’t get anything wet. Also you can use a can of compressed air, such as is used for electronics, to clear debris.
Check for any loose wires or terminal screws inside the thermostat. Make sure wires aren’t corroded or detached. Never remove the thermostat cover without removing the batteries or turning off the power at the fuse or breaker box. Tighten screws and secure loose wires if needed.
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Answer:
The ball thrown downward
Explanation:
When the ball is thrown vertically, the acceleration of it is the gravity acceleration independent if it is thrown downward or upward. However, the acceleration is a vector, so, when the ball is thrown upward, the movement is against the gravity, so the acceleration is negative, and so, the velocity decreases during time; and when the ball is thrown downward, the movement goes to the gravity, so the acceleration is positive, so the velocity increase after time passes.
