CMT CMT Battery & Power Management 2

Question 1

What is the recommended storage charge level for a Li-Ion battery if a device will not be used for an extended period?

Accepted Answer

Approximately 40–60%

Answer

100% (fully charged)

Answer

0% (fully discharged)

Answer

Exactly 75%

Question 2

Which USB Power Delivery (USB-PD) feature allows a device to act as both a charger and a chargeable device?

Accepted Answer

Dual-Role Power (DRP)

Answer

Battery Charge Specification 1.2

Answer

Voltage Regulator Mode

Answer

Passive Power Switching

Question 3

What unit is used to measure the rate of charge or discharge of a battery relative to its capacity?

Accepted Answer

C-rate

Answer

Watt-hour (Wh)

Answer

Ampere (A)

Answer

Coulomb (C)

Question 4

What does the Battery Management System (BMS) in a smartphone primarily control?

Accepted Answer

Charging voltage, current, temperature, and cell balancing to protect battery health

Answer

CPU power states and thermal throttling only

Answer

Screen brightness based on ambient light

Answer

Wireless radio power output levels

Question 5

Wireless charging in smartphones most commonly uses which technology standard?

Accepted Answer

Qi (pronounced 'chee') inductive charging

Answer

Bluetooth Low Energy (BLE) power transfer

Answer

Near Field Communication (NFC) charging

Answer

Radio Frequency Identification (RFID) power harvesting

Question 6

Which setting on a smartphone most significantly reduces battery drain during periods of inactivity?

Accepted Answer

Enabling Airplane Mode when not in use

Answer

Disabling auto-rotate

Answer

Turning off autocorrect

Answer

Disabling screenshot shortcuts

Question 7

What is 'trickle charging' in the context of mobile battery management?

Accepted Answer

A slow, low-current charge applied to maintain a fully charged battery or recover a deeply discharged cell

Answer

Charging at maximum current until 100% is reached

Answer

A fast-charge protocol that alternates between high and low current

Answer

Charging multiple devices simultaneously at reduced speed