Energy can be determined using the formula power multiplied by time, thus for a power of 1200 W (or 1200 Joules per second) and a duration of 30 seconds, the calculation yields 36000 J or 36 kJ of electrical energy.
If you need the electrical charge or current: Power equals voltage times current. Therefore, with a power of 1200 watts and a voltage of 120 V, the current can be found as 1200 W divided by 120 V, which results in 10 Amperes. The charge is obtained by multiplying 10 A by 30 s, yielding 300 C.
The sheet's charge density calculates to be 1.384×10⁻⁷C/m².
Charge density is the ratio of charge per unit area.
The square sheet has dimensions l=17 cm.
To compute the area A of the sheet.
The overall charge Q on the sheet is
The charge density σ is defined as
We substitute 4×10⁻⁹C for Q and 0.0289 m² for A.
Thus, the charge density for the sheet is 1.384×10⁻⁷C/m².
A block weighing m1 = 4.50 kg and a ball weighing m2 = 7.70 kg are linked by a light string over a frictionless pulley, as illustrated in figure (a). The coefficient of kinetic friction between the block and the surface is 0.300.
(a) Determine the acceleration of both objects and the tension present in the string.
(b) Verify the acceleration calculation using a systems approach. (Utilize m1, m2, μk, and g as needed.)
(c) If an additional mass is added to the ball, what amount is necessary to augment the downward acceleration by 60%?
In (a), I calculated the acceleration to be 5.10 m/s^2 and the tension to be 36.2N.
In (b), the equation used is a = (m2g-ukm1g)/(m1+m2)
It’s (c) that I am struggling to understand. Can anyone assist me?
