Answer:
90 W
Explanation:
The power of the light bulb is given by:
where
V is the voltage of the bulb
I is the current through the bulb
In this problem,
V = 120 V
I = 0.75 A
Substituting into the equation,
The correct answer is 2.479
Thermometer-temperature
Wind vane -wind direction
Anemometer- both wind speed (and direction)
Hygrometer- humidity
Answer:
The speed of the ball when it hits the ground is 102.1 m/s
Explanation:
Given;
initial velocity of ball, u = 25 m/s
distance traveled by the ball = height of the building = h = 500 m
when the ball hits the ground, the final velocity, v = ?
The final velocity of the ball is given by;
v² = u² + 2gh
where;
g is acceleration due to gravity = 9.8 m/s²
v² = (25)² + 2(9.8)(500)
v² = 10425
v = √10425
v = 102.1 m/s
Therefore, the speed of the ball when it hits the ground is 102.1 m/s
Answer:
Explanation:
The bead is moving on a vertical circular path so it must have a centripetal force towards the centre.
This force is equal to m v² / r
v is velocity of bead and r is radius of the circular path.
The vertical hoop is also rotating about a vertical axis passing through the centre at frequency f so the bead will experience a cetrifugal force due to rotation of the hoop. Its value is
m ω² r . Only at the point o degree and 180 degree , these forces are opposite to each other so at these points , the bead will be in equilibrium .
mv² / r = m ω² r
v² = ω² r²
v = ω r
= 2π f r
= 2 x 3.14 x 2 x 0.22
v = 2.76 m /s
For the bead to rise upto point θ = 90 degree , height achieved is radius R
required velocity = √ 2gR
= √ 2x 9.8x.22
= 2.076 m/s
This velocity is less than the velocity calculated earlier so the bead will be able to ride the required height.
v = 2.76 m/s
