find the energy in kWh consumed in 10 hours by four devices of power 500 W each.

Explanation

To solve the problem of finding the energy consumed in kilowatt-hours (kWh) by four devices of power 500 W each over a period of 10 hours, we can follow these steps:

### Step 1: Calculate the total power consumed by the devices.
Each device has a power of 500 W. Since there are 4 devices, the total power (P_total) can be calculated as:
\[ P_{\text{total}} = \text{Number of devices} \times \text{Power of each device} = 4 \times 500 \, \text{W} \]
\[ P_{\text{total}} = 2000 \, \text{W} \]

### Step 2: Convert the total power from watts to kilowatts.
Since 1 kW = 1000 W, we convert the total power to kilowatts (kW):
\[ P_{\text{total}} = \frac{2000 \, \text{W}}{1000} = 2 \, \text{kW} \]

### Step 3: Calculate the energy consumed over the given time.
The energy consumed (W) can be calculated using the formula:
\[ W = P \times t \]
where \(P\) is the power in kilowatts and \(t\) is the time in hours. Here, \(t = 10\) hours:
\[ W = 2 \, \text{kW} \times 10 \, \text{hours} = 20 \, \text{kWh} \]

### Final Answer:
The energy consumed by the four devices in 10 hours is **20 kWh**.

---