Logical Shifts Flashcards

1️⃣ Familiarise yourself with the flashcards:

  • Look through all the flashcards to see what's on both sides.
  • Make sure you understand the information on each card. If something's unclear, click the link to the revision notes at the bottom of the page for more details.

2️⃣ Test yourself:

  • Look at the question or prompt on each card and try to remember the answer before flipping it over.
  • Check the answer and make a note of any cards you find challenging and need to go over more.

3️⃣ Consistently Review and Practice:

  • Use spaced repetition: spend more time on the cards you struggle with and go over them more often.
  • Regularly review all the flashcards to help you better understand and retain the information over time.

Note: We may include questions that have multiple correct answers. It's useful to remember specific examples to understand these concepts better.

PERSONALISED 1-TO-1 TUTORING

Need more help on this topic? Get 1-to-1 support

Get support with clear explanations, practice and feedback (Ages 5 to 16).

  • DBS-checked tutors
  • Flexible times
  • Parents can be updated

Want an ad-free experience? Subscribe to remove ads

What is a logical left shift?

Move every bit one place left, drop the leftmost bit, and put a 0 on the right.

What is a logical right shift?

Move every bit one place right, drop the rightmost bit, and put a 0 on the left.

In unsigned binary, what does a logical left shift by 1 do to the value?

It multiplies the value by 2.

In unsigned binary, what does a logical right shift by 1 do to the value?

It divides the value by 2 and rounds down.

What do MSB and LSB mean?

MSB is the most significant bit (leftmost). LSB is the least significant bit (rightmost).

What is overflow in a logical left shift?

When a 1 moves past the MSB and is lost, the true value cannot fit in the fixed number of bits.

What happens to an odd number when you do a logical right shift by 1?

It is divided by 2 and the remainder is lost. For example, 13 becomes 6.

How do you do a logical left shift by 2 on an 8-bit number?

Move all bits two places left, drop the two leftmost bits, and add two 0s on the right.

How does shifting by n places change an unsigned value?

Left shift by n multiplies by 2 to the power of n. Right shift by n divides by 2 to the power of n and rounds down.

What is the result of shifting 10010001 right by 3 using a logical shift?

00010010

What is the result of shifting 00110110 left by 2 using a logical shift?

11011000