Input devices (keyboard, mouse, touchscreen) in Intro to Computing - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

How does a keyboard send input to a computer?

Imagine typing on a keyboard. What happens inside the computer when you press a key?

A The keyboard stores the characters and sends them all at once when you press Enter.

B The keyboard sends images of the keys pressed to the computer for processing.

C The keyboard sends sound waves to the computer, which converts them into text.

D The keyboard sends electrical signals to the computer, which the computer translates into characters.

💡 Hint

Think about how pressing a key can be understood by the computer instantly.

When you press a key, the keyboard sends an electrical signal representing that key to the computer. The computer then converts this signal into the corresponding character.

❓ trace

intermediate

Trace the input flow from mouse click to action

When you click a mouse button, what is the correct sequence of events inside the computer?

A 1,2,3,4

B 2,1,3,4

C 1,3,2,4

D 3,2,1,4

💡 Hint

Think about what happens first and how the signal flows.

First, the mouse button is pressed. Then the mouse sends an electrical signal to the computer. The computer processes this signal and performs the action on the screen.

❓ identification

advanced

Identify the input device from its description

Which input device uses a grid of sensors to detect the position and pressure of your finger?

A Keyboard

B Touchscreen

C Mouse

D Microphone

💡 Hint

It lets you tap or swipe directly on the display.

A touchscreen uses a grid of sensors to detect where and how hard you touch the screen, allowing direct interaction.

❓ Comparison

advanced

Compare how mouse and touchscreen detect input

Which statement correctly compares how a mouse and a touchscreen detect user input?

A Both mouse and touchscreen detect input by sending sound waves to the computer.

B A mouse detects input by sensing finger position on the screen; a touchscreen detects movement by tracking a ball.

C A mouse detects movement by tracking a ball or sensor movement; a touchscreen detects input by sensing finger position on the screen.

D A mouse and touchscreen both use keyboards to detect input.

💡 Hint

Think about how you move a mouse versus how you touch a screen.

A mouse detects movement by tracking physical movement (like a ball or optical sensor). A touchscreen detects input by sensing where your finger touches the screen.

🚀 Application

expert

Determine the output when combining input devices

Consider a computer program that accepts input from both a keyboard and a touchscreen. The program waits for a key press or a screen tap. If the user taps the screen at position (150, 300), and then presses the 'Enter' key, what will the program receive in order?

A First the coordinates (150, 300), then the 'Enter' key signal.

B First the 'Enter' key signal, then the coordinates (150, 300).

C Only the 'Enter' key signal, because touchscreen input is ignored.

D Only the coordinates (150, 300), because keyboard input is ignored.

💡 Hint

Think about the order of user actions and how input devices send signals.

The program receives input in the order the user provides it: first the touchscreen tap coordinates, then the keyboard 'Enter' key signal.