Science 8- Pre Test

An object vertically thrown upward in air have the following characteristics except

• Initial velocity is equal to initial vertical velocity.

• Horizontal velocity is zero.

• Vertical upward velocity is decreasing.

• Acceleration due to gravity at maximum height is equal to zero.

An automobile travelling at 50km/h North turns a curve to the west maintaining 50 km/h. The automobile is travelling with

• constant velocity.

• constant speed.

• constant acceleration.

• constant direction.

A car moving with a constant acceleration is moving

• at the same direction.

• at the same speed.

• at the same velocity.

• Increasing speed with constant increase per unit time.

Which of the following quantities is a vector quantity?

• A weight of 20 N

• A speed of 90 km/h

• A mass of 60 kg

• A temperature of 37°C

Sixty million stars is expressed in scientific notations as

• 60.0 x 10€ stars

• 6.0 × 10- stars

• 6.0 x 10' stars

• 60.0 x 10* stars

Which of the following waves move perpendicularly to the particles of the medium?

• Amplitude

• Longitudinal

• Transverse

• Frequency

Which characteristics of the waves are inversely proportional?

• Amplitude and wavelength

• Frequency and period

• Wavelength and wave speed

• Amplitude and period

The frequency of hearing of humans is 20 000 hertz. Dolphins have 130 000 hz, Frogs have 3 000 hz. Chimps have 20 000 hz and Pigeons have 10 000 hz. Which frequency is ultrasonic to humans?

• Chimp

• Dolphins

• Frogs

• Pigeons

Why do men tend to have a deeper voice than women? Their vocal chord is

• Longer and thicker vocal chords.

• Shorter and thinner vocal chords.

• Longer and thinner.

• Shorter and thicker.

What is the acceleration of an object when it reaches the maximum height?

• 9.81 m/s^2
• 12 m/s^2
• 5 m/s^2
• 0 m/s^2