WGU C952 Computer Architecture Objective Assessment Practice
Questions and Answers (Sets 1-5) | Latest 2026 Update | Graded
A+ | 50 MCQ with Explanations
1. What does Amdahl’s Law primarily determine?
a) The maximum clock speed of a processor
b) The maximum theoretical speedup from parallelization
c) The minimum cache size required
d) The power consumption of a system
Explanation: Amdahl’s Law calculates the upper limit of performance improvement when
only part of a system is enhanced, based on the fraction of time that part is used.
2. A program spends 80% of its time on a task that can be parallelized. What is the
maximum speedup using an infinite number of processors?
a) 2x
b) 4x
c) 5x
d) 10x
*Explanation: Speedup = 1 / (1 - P) where P = 0.8, so .2 = 5.*
3. A CPU has a clock cycle time of 0.5 ns. What is its clock rate?
a) 500 MHz
b) 1 GHz
c) 2 GHz
d) 4 GHz
*Explanation: Clock rate = 1 / cycle time = 1 / (0.5 × 10⁻⁹) = 2 × 10⁹ Hz = 2 GHz.*
4. A program takes 10 seconds to run on CPU A with a 2 GHz clock. CPU B runs the
same program in 8 seconds. What is the speedup of CPU B over CPU A?
a) 0.8x
b) 1.25x
c) 2x
, d) 10x
*Explanation: Speedup = Time_A / Time_B = = 1.25.*
5. If a CPU’s clock rate doubles, what happens to execution time for the same
program?
a) Doubles
b) Halves (ideally)
c) Remains the same
d) Increases by 50%
Explanation: Execution time is inversely proportional to clock rate, assuming no other
changes.
6. Which metric directly measures CPU performance?
a) MIPS
b) Execution time
c) Clock rate
d) Number of transistors
Explanation: Execution time (seconds per program) is the true measure of performance.
7. A program has 5 billion instructions. The CPI is 1.2 and clock rate is 2 GHz. What
is execution time?
a) 1 second
b) 3 seconds
c) 5 seconds
d) 10 seconds
*Explanation: CPU time = (Instructions × CPI) / Clock rate = (5e9 × 1.2) / (2e9) = 6e9 /
2e9 = 3 seconds.*
8. Which is a valid CPU performance equation?
a) Time = Instructions × CPI × Clock rate
b) Time = Instructions × CPI / Clock rate
c) Time = (Instructions × Clock rate) / CPI
Questions and Answers (Sets 1-5) | Latest 2026 Update | Graded
A+ | 50 MCQ with Explanations
1. What does Amdahl’s Law primarily determine?
a) The maximum clock speed of a processor
b) The maximum theoretical speedup from parallelization
c) The minimum cache size required
d) The power consumption of a system
Explanation: Amdahl’s Law calculates the upper limit of performance improvement when
only part of a system is enhanced, based on the fraction of time that part is used.
2. A program spends 80% of its time on a task that can be parallelized. What is the
maximum speedup using an infinite number of processors?
a) 2x
b) 4x
c) 5x
d) 10x
*Explanation: Speedup = 1 / (1 - P) where P = 0.8, so .2 = 5.*
3. A CPU has a clock cycle time of 0.5 ns. What is its clock rate?
a) 500 MHz
b) 1 GHz
c) 2 GHz
d) 4 GHz
*Explanation: Clock rate = 1 / cycle time = 1 / (0.5 × 10⁻⁹) = 2 × 10⁹ Hz = 2 GHz.*
4. A program takes 10 seconds to run on CPU A with a 2 GHz clock. CPU B runs the
same program in 8 seconds. What is the speedup of CPU B over CPU A?
a) 0.8x
b) 1.25x
c) 2x
, d) 10x
*Explanation: Speedup = Time_A / Time_B = = 1.25.*
5. If a CPU’s clock rate doubles, what happens to execution time for the same
program?
a) Doubles
b) Halves (ideally)
c) Remains the same
d) Increases by 50%
Explanation: Execution time is inversely proportional to clock rate, assuming no other
changes.
6. Which metric directly measures CPU performance?
a) MIPS
b) Execution time
c) Clock rate
d) Number of transistors
Explanation: Execution time (seconds per program) is the true measure of performance.
7. A program has 5 billion instructions. The CPI is 1.2 and clock rate is 2 GHz. What
is execution time?
a) 1 second
b) 3 seconds
c) 5 seconds
d) 10 seconds
*Explanation: CPU time = (Instructions × CPI) / Clock rate = (5e9 × 1.2) / (2e9) = 6e9 /
2e9 = 3 seconds.*
8. Which is a valid CPU performance equation?
a) Time = Instructions × CPI × Clock rate
b) Time = Instructions × CPI / Clock rate
c) Time = (Instructions × Clock rate) / CPI
