Chapter 1: Physical Quantities and Measurements

By using prefixes, we can write 335 × 10^-8 s as

• 0.335 µs

• 33.5 µs

• 335 µs

• 3.35 µs

Find the vector product of  $A=3i-3j+k\ and\ B=-2i-2j-3k$  

•  $11i+7j+12k$  

•  $11i+7j-12k$  

•  $11i-7j-12k$  
  

•  $-11i+7j+12k$  
  

A chips wrapper is 4.5 cm long and 5.9 cm wide. Its area up to significant figures will be

• 30 cm²

• 28 cm²

• 26.55 cm²

• 32 cm²

By converting 3 700 000 Watt into kilowatt, we get

• 3.7 W

• 3 700 kW

• 3 7000 kW

• 37 kW

Calculate the horizontal and vertical components of a 50 N force which is acting 40° to the horizontal.

• Horizontal: 38.30 N; Vertical: 32.14 N

• Horizontal: 40 N; Vertical: 35 N

• Horizontal: 30.30 N; Vertical: 30.14 N

• Horizontal: 28.30 N; Vertical: 32.14 N

What are the x and y components of the plane's velocity?

• $v_x=38.6\ m\ s^{-1}\ ;\ v_y=10.4\ m\ s^{-1}$

• $v_x=50.5\ m\ s^{-1}\ ;\ v_y=15.4\ m\ s^{-1}$

• $v_x=20.5\ m\ s^{-1}\ ;\ v_y=10.4\ m\ s^{-1}$

• $v_x=10.4\ m\ s^{-1}\ ;\ v_y=38.6\ m\ s^{-1}$

Find the magnitude and direction of -30i + 27j

• 23.3 ; 300° from the x-axis

• 40.4 ; 138° from the x-axis

• 25.3 ; 350° from the x-axis

• 30 ; 270° from the x-axis

What are superman's x and y component?

• $x=86.6\ m\ ;\ y=-50\ m$

• $x=86.6\ cm\ ;\ y=-50\ cm$

• $x=-86.6\ m\ ;\ y=-50\ m$

• $x=86.6\ m\ ;\ y=50\ m$

The dimensions for speed is ...

• $L\ T^{-1}$

• $L^2\ T^{-1}$

• $L^2\ T^{-2}$

• $L\ T$

The dimensions of power is ...

• $M\ L^2\ T^{-3}$

• $M\ L^2\ T^{-2}$

• $M\ \ L^2\ T^{ }$

• $M\ ^{-1}\ L^2\ T^{-3}$