<h2>
Energy used by heater is 8.21 x 10⁶ J</h2>
Explanation:
Energy = Power x Time
Power = Voltage x Current
Voltage = 120 V
Current = 9.5 A
Power = Voltage x Current
Power = 120 x 9.5 = 1140 W
Time = 2 hours = 2 x 60 x 60 = 7200 s
Energy = Power x Time
Energy = 1140 x 7200
Energy = 8208000 J
Energy used by heater is 8.21 x 10⁶ J
We actually don't need to know how far he/she is standing from the net, as we know that the ball reaches its maximum height (vertex) at the net. At the vertex, it's vertical velocity is 0, since it has stopped moving up and is about to come back down, and its displacement is 0.33m. So we use v² = u² + 2as (neat trick I discovered just then for typing the squared sign: hold down alt and type 0178 on ur numpad wtih numlock on!!!) ANYWAY....... We apply v² = u² + 2as in the y direction only. Ignore x direction.
IN Y DIRECTION: v² = u² + 2as 0 = u² - 2gh u = √(2gh) (Sub in values at the very end)
So that will be the velocity in the y direction only. But we're given the angle at which the ball is hit (3° to the horizontal). So to find the velocity (sum of the velocity in x and y direction on impact) we can use: sin 3° = opposite/hypotenuse = (velocity in y direction only) / (velocity) So rearranging, velocity = (velocity in y direction only) / sin 3° = √(2gh)/sin 3° = (√(2 x 9.8 x 0.33)) / sin 3° = 49 m/s at 3° to the horizontal (2 sig figs)
Answer:Near-field communication
Explanation:
Near Field Communication is an umbrella term that applies to location-aware technologies that allow devices to communicate securely with each other over short distances. Near-field communication is a short-range wirelessconnectivity standard that uses magnetic field induction to enable communication between devices when they're touched together, or brought within a few centimeters to each other.It also specifies a way for the devices to establish a peer-to-peer network to exchange data. After the peer to peer network has been configured, another wireless communication technology, such as Bluetooth or Wi-Fi, can be used for longer-range communication or for transferring larger amounts of data.
Answer:
16 m/s
Explanation:
Given that
y momentum = 0.080 *25 = 2
x momentum = 0.075*20 = 1.5
total momentum = √(4 + 2.25)
Total momentum = √6.25
Total momentum = 2.5
total mass = mass of x and y momentum = 0.075 + 0.080 = 0.155
speed of mass center = total momentum / total mass = 2.5/0.155 = 16.
And thus, the speed of the center of mass of this two-particle system at this instant is 16 m/s
