Tag: science & technology

Quizzes (551) Questions (11015)

Questions Related to science & technology

Multiple choice general knowledge science & technology

A car is retarding. So it must be

  1. slowing down

  2. speeding in opposite direction

  3. both of them are true

  4. only one of them is true
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A car is retarding when its velocity is decreasing. This can happen by slowing down in the current direction OR by speeding in the opposite direction (since velocity includes direction). Therefore, both scenarios are valid examples of retardation.

Multiple choice general knowledge science & technology

We have two lamps: one is broken (A), the other is glowing (B). Which of these lamps is emitting electromagnetic radiation?

  1. Lamp A

  2. Lamp B

  3. Both

  4. Neither
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

All objects with temperature above absolute zero emit electromagnetic radiation (thermal radiation). Lamp B (glowing) emits visible light plus thermal radiation. Lamp A (broken but still at room temperature) still emits thermal radiation in the infrared spectrum. Therefore, both lamps emit electromagnetic radiation.

Multiple choice general knowledge science & technology

Everybody knows that 'water seeks its own level' but very few people know why water seeks its own level. The reason has most to do with

  1. atmospheric pressure

  2. water pressure depending on depth

  3. water's density

  4. value of 'g'
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Water seeks its own level due to water pressure increasing with depth (P = rho * g * h). In connected vessels, water flows until pressures at the same horizontal level equalize, which occurs when water surfaces are at the same height. Atmospheric pressure is the same on all surfaces and cancels out, while density and 'g' don't determine level-seeking behavior.

Multiple choice general knowledge science & technology

A birthday candle burns in a deep drinking glass. When the glass is whirled around in a circular path, which way does the candle flame point?

  1. Towards the centre

  2. Outwards

  3. It will remain still

  4. It will oscillate inwards and outwards
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When the glass is whirled in a circular path, the flame points toward the center due to inertia. The more massive gases in the flame have greater inertia and resist the circular motion more than the lighter glass and air, causing them to lag inward relative to the center of rotation.

Multiple choice general knowledge science & technology

If you release a ball inside a freely-falling elevator it stays in front of you instead of "falling to the floor" because you, the ball, and the elevator are all accelerating downward at the same acceleration, g. If you similarly release a helium-filled balloon, the balloon will--

  1. press against the ceiling

  2. press against the floor

  3. squeeze and blast due to non-uniform air pressure

  4. also stay in front of you
Reveal answer Fill a bubble to check yourself
D Correct answer
Multiple choice general knowledge science & technology

Consider a boat loaded with scrap iron in a swimming pool. If the iron is thrown overboard into the pool, will the water level at the edge of the pool rise, fall, or remain unchanged?

  1. fall

  2. rise

  3. remain same

  4. impossible to tell
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When iron is in the boat, it displaces water equal to its weight. When submerged, it displaces water equal to its volume. Since iron is denser than water, its volume is less than the volume of water with the same weight, so less water is displaced overall.

Multiple choice general knowledge science & technology

An astronaut on earth notes that in her soft drink an ice cube floats with 9/10 its volume submerged. If she were instead in a lunar module parked on the moon, the ice in the same soft drink would float with

  1. less than 9/10 submerged.

  2. 9/10 submerged.

  3. more than 9/10 submerged.

  4. impossible to tell
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The fraction of an ice cube submerged depends only on the density ratio of ice to liquid, not on gravitational acceleration. This ratio is unchanged on the moon, so the submerged volume remains 9/10.