CBP Bitcoin Mining and Consensus 2

Question 1

What is the primary purpose of the nonce field in a Bitcoin block header?

Accepted Answer

To provide a value miners iterate over to find a valid hash

Answer

To identify the miner who found the block

Answer

To store transaction fee totals

Answer

To encode the block's timestamp

Question 2

What happens to the Bitcoin block subsidy approximately every 210,000 blocks?

Accepted Answer

It is cut in half

Answer

It doubles

Answer

It resets to the genesis amount

Answer

It is eliminated entirely

Question 3

Which consensus rule determines which chain Bitcoin nodes consider valid when two chains of equal length exist?

Accepted Answer

The chain with the most accumulated proof-of-work

Answer

The chain with the most transactions

Answer

The chain with the lowest difficulty

Answer

The chain created by the oldest node

Question 4

What is an 'orphan block' in Bitcoin mining?

Accepted Answer

A valid block that is not part of the main chain because another block won the race

Answer

A block with no transactions

Answer

A block whose miner is unknown

Answer

A block containing invalid transactions

Question 5

What is the significance of the 'extraNonce' field used by miners?

Accepted Answer

It extends the nonce search space within the coinbase transaction

Answer

It stores the miner's wallet address

Answer

It records the pool's fee percentage

Answer

It encodes the software version used

Question 6

Which of the following best describes 'selfish mining'?

Accepted Answer

Withholding discovered blocks to gain a competitive advantage over honest miners

Answer

Mining without joining a pool

Answer

Charging extra fees for transaction inclusion

Answer

Using more energy than average per hash

Question 7

What is the target block interval Bitcoin's difficulty adjustment aims to maintain?

Accepted Answer

10 minutes

Answer

1 minute

Answer

5 minutes

Answer

30 minutes