18 Authentication questions from the Firebase bank, written for Indian campus drives and tech interviews. Every question has a verified answer and an AI-tutor explanation on placd.
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A.extra key-value attributes set on a user via the Admin SDK to encode roles, then read inside security rules for authorization
B.the managed service that signs users in with email/password, phone, or federated providers and returns a verified identity
C.a short-lived signed JWT minted on sign-in that the client sends to prove who it is, verifiable on the backend
D.a method that issues a temporary account with a real UID so a guest can use the app before upgrading to a permanent login
Answer + AI explanation with Pro
2. Which term means: "the managed service that signs users in with email/password, phone, or federated providers and returns a verified identity"?
Junior
A.Firebase Auth
B.Identity provider
C.ID token
D.Custom claims
Answer + AI explanation with Pro
3. Which statement is correct?
Junior
A.Firebase Auth — extra key-value attributes set on a user via the Admin SDK to encode roles, then read inside security rules for authorization
B.Firebase Auth — the managed service that signs users in with email/password, phone, or federated providers and returns a verified identity
C.Firebase Auth — a short-lived signed JWT minted on sign-in that the client sends to prove who it is, verifiable on the backend
D.Firebase Auth — the SDK process of silently exchanging a long-lived credential for a new ID token roughly every hour as the old one expires
Answer + AI explanation with Pro
4. What is Identity provider?
Junior
A.the SDK process of silently exchanging a long-lived credential for a new ID token roughly every hour as the old one expires
B.a method that issues a temporary account with a real UID so a guest can use the app before upgrading to a permanent login
C.an external source such as Google, Apple, or Facebook that vouches for a user during a federated sign-in flow
D.extra key-value attributes set on a user via the Admin SDK to encode roles, then read inside security rules for authorization
Answer + AI explanation with Pro
5. Which term means: "an external source such as Google, Apple, or Facebook that vouches for a user during a federated sign-in flow"?
Junior
A.Anonymous sign-in
B.Firebase Auth
C.Identity provider
D.Token refresh
Answer + AI explanation with Pro
6. Which statement is correct?
Junior
A.Identity provider — a short-lived signed JWT minted on sign-in that the client sends to prove who it is, verifiable on the backend
B.Identity provider — a method that issues a temporary account with a real UID so a guest can use the app before upgrading to a permanent login
C.Identity provider — extra key-value attributes set on a user via the Admin SDK to encode roles, then read inside security rules for authorization
D.Identity provider — an external source such as Google, Apple, or Facebook that vouches for a user during a federated sign-in flow
Answer + AI explanation with Pro
7. What is Anonymous sign-in?
Mid
A.an external source such as Google, Apple, or Facebook that vouches for a user during a federated sign-in flow
B.extra key-value attributes set on a user via the Admin SDK to encode roles, then read inside security rules for authorization
C.the SDK process of silently exchanging a long-lived credential for a new ID token roughly every hour as the old one expires
D.a method that issues a temporary account with a real UID so a guest can use the app before upgrading to a permanent login
Answer + AI explanation with Pro
8. Which term means: "a method that issues a temporary account with a real UID so a guest can use the app before upgrading to a permanent login"?
Mid
A.Anonymous sign-in
B.Identity provider
C.Custom claims
D.Token refresh
Answer + AI explanation with Pro
9. Which statement is correct?
Mid
A.Anonymous sign-in — a short-lived signed JWT minted on sign-in that the client sends to prove who it is, verifiable on the backend
B.Anonymous sign-in — an external source such as Google, Apple, or Facebook that vouches for a user during a federated sign-in flow
C.Anonymous sign-in — a method that issues a temporary account with a real UID so a guest can use the app before upgrading to a permanent login
D.Anonymous sign-in — the managed service that signs users in with email/password, phone, or federated providers and returns a verified identity
Answer + AI explanation with Pro
10. What is ID token?
Mid
A.a method that issues a temporary account with a real UID so a guest can use the app before upgrading to a permanent login
B.a short-lived signed JWT minted on sign-in that the client sends to prove who it is, verifiable on the backend
C.extra key-value attributes set on a user via the Admin SDK to encode roles, then read inside security rules for authorization
D.the managed service that signs users in with email/password, phone, or federated providers and returns a verified identity
Answer + AI explanation with Pro
11. Which term means: "a short-lived signed JWT minted on sign-in that the client sends to prove who it is, verifiable on the backend"?
Mid
A.Anonymous sign-in
B.Token refresh
C.ID token
D.Custom claims
Answer + AI explanation with Pro
12. Which statement is correct?
Mid
A.ID token — the managed service that signs users in with email/password, phone, or federated providers and returns a verified identity
B.ID token — a short-lived signed JWT minted on sign-in that the client sends to prove who it is, verifiable on the backend
C.ID token — the SDK process of silently exchanging a long-lived credential for a new ID token roughly every hour as the old one expires
D.ID token — an external source such as Google, Apple, or Facebook that vouches for a user during a federated sign-in flow
Answer + AI explanation with Pro
13. What is Custom claims?
Senior
A.a method that issues a temporary account with a real UID so a guest can use the app before upgrading to a permanent login
B.a short-lived signed JWT minted on sign-in that the client sends to prove who it is, verifiable on the backend
C.extra key-value attributes set on a user via the Admin SDK to encode roles, then read inside security rules for authorization
D.an external source such as Google, Apple, or Facebook that vouches for a user during a federated sign-in flow
Answer + AI explanation with Pro
14. Which term means: "extra key-value attributes set on a user via the Admin SDK to encode roles, then read inside security rules for authorization"?
Senior
A.ID token
B.Firebase Auth
C.Token refresh
D.Custom claims
Answer + AI explanation with Pro
15. Which statement is correct?
Senior
A.Custom claims — a short-lived signed JWT minted on sign-in that the client sends to prove who it is, verifiable on the backend
B.Custom claims — the SDK process of silently exchanging a long-lived credential for a new ID token roughly every hour as the old one expires
C.Custom claims — extra key-value attributes set on a user via the Admin SDK to encode roles, then read inside security rules for authorization
D.Custom claims — a method that issues a temporary account with a real UID so a guest can use the app before upgrading to a permanent login
Answer + AI explanation with Pro
16. What is Token refresh?
Senior
A.the managed service that signs users in with email/password, phone, or federated providers and returns a verified identity
B.a method that issues a temporary account with a real UID so a guest can use the app before upgrading to a permanent login
C.the SDK process of silently exchanging a long-lived credential for a new ID token roughly every hour as the old one expires
D.an external source such as Google, Apple, or Facebook that vouches for a user during a federated sign-in flow
Answer + AI explanation with Pro
17. Which term means: "the SDK process of silently exchanging a long-lived credential for a new ID token roughly every hour as the old one expires"?
Senior
A.Token refresh
B.Anonymous sign-in
C.ID token
D.Firebase Auth
Answer + AI explanation with Pro
18. Which statement is correct?
Senior
A.Token refresh — the managed service that signs users in with email/password, phone, or federated providers and returns a verified identity
B.Token refresh — extra key-value attributes set on a user via the Admin SDK to encode roles, then read inside security rules for authorization
C.Token refresh — the SDK process of silently exchanging a long-lived credential for a new ID token roughly every hour as the old one expires
D.Token refresh — an external source such as Google, Apple, or Facebook that vouches for a user during a federated sign-in flow
Answer + AI explanation with Pro
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