Answer:
(a) 3107.98 J
(b) 14530.6 J
Explanation:
mass, m = 3.56 kg
angular speed, ω = 179 rad/s
Moment of inertia of solid cylinder, I = 1/2 mr^2
where, m is the mass and r be the radius of the cylinder.
(a) radius, r = 0.330 m
I = 0.5 x 3.56 x 0.330 x 0.330 = 0.194 kgm^2
The formula for the rotational kinetic energy is given by
K = 0.5 x 0.194 x 179 x 179 = 3107.98 J
(b) radius, r = 0.714 m
I = 0.5 x 3.56 x 0.714 x 0.714 = 0.907 kgm^2
The formula for the rotational kinetic energy is given by
K = 0.5 x 0.907 x 179 x 179 = 14530.6 J
Answer:
Resistance = 1728.57 Ohms
Explanation:
Given the following data;
Power = 7 Watts
Voltage = 110 Volts
To find the resistance of each bulb;
Mathematically, power can be calculated using the formula;
Making resistance the subject of formula, we have;
Substituting into the formula, we have;
Resistance = 1728.57 Ohms
Answer:
0.2 J
Explanation:
The pendulum forms a right triangle, with hypotenuse of 50 cm and base of 30 cm. The height of this triangle can be found with Pythagorean theorem:
c² = a² + b²
(50 cm)² = a² + (30 cm)²
a = 40 cm
The height of the triangle is 40 cm. The height of the pendulum when it is at the bottom is 50 cm. So the end of the pendulum is lifted by 10 cm. Assuming the mass is concentrated at the end of the pendulum, the potential energy is:
PE = mgh
PE = (0.200 kg) (9.8 N/kg) (0.10 m)
PE = 0.196 J
Rounding to one significant figure, the potential energy is 0.2 J.
Current = Power/Voltage. 70W/120v= 0.583 Amps.
Translation
A tractor pulling a cart loaded with sugar cane travels down the straight path of a farm at a speed of 20 km / h. If at 3:00 p.m.you pass the Finca Las Margaritas, what time will you arrive at the Las Ilusiones farm, located on the same road, if the distance between the two farms is 60 km
Answer:
6.00 pm
Explanation:
Speed is given by dividing distance by time and expressed as s=d/t. Making time the subject of the formula then t=d/s where s is the speed, d is distance covered and t is the time taken. Substituting 20 km/h for s and 60 km for d then t=60/20=3 hours
Adding 3 hours to 3 pm we get 6pm
Therefore, the time to reach the destination if the speed is constantly maintained is 6.00 pm
