FREE Blockchain Developer Blockchain Fundamentals and Cryptography Questions and Answers Flashcards
6 cards from real Blockchain Technology practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 FREE Blockchain Developer Blockchain Fundamentals and Cryptography Questions and Answers flashcards as text
What is the primary purpose of a Merkle tree in blockchain technology?
Answer: To efficiently verify the integrity of large datasets
Merkle trees allow efficient and secure verification of data integrity by organizing transaction hashes into a binary tree structure where any change propagates to the root.
Which cryptographic property ensures that even a single-bit change in input produces a completely different hash output?
Answer: Avalanche effect
The avalanche effect means that a small change in input causes a drastic change in the hash output, making it practically impossible to predict modifications.
In a proof-of-work consensus mechanism, what does the nonce value represent?
Answer: A variable miners adjust to find a valid block hash
The nonce is an arbitrary number that miners repeatedly change to produce a block hash that meets the network's difficulty target.
What type of cryptography does Bitcoin use for generating wallet addresses and signing transactions?
Answer: Elliptic Curve Digital Signature Algorithm (ECDSA)
Bitcoin uses ECDSA with the secp256k1 curve to create public-private key pairs and digitally sign transactions.
What is a 51% attack in blockchain?
Answer: When a single entity controls the majority of mining power and can manipulate the chain
A 51% attack occurs when an attacker gains majority hash rate control, enabling them to reverse transactions and double-spend coins.
Which data structure links blocks together to form an immutable chain?
Answer: Each block containing the cryptographic hash of the previous block's header
Each block header includes the hash of the previous block's header, creating a tamper-evident chain where altering any block invalidates all subsequent blocks.