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Fill in the blanks by suitable conversion of units

(c) 3.0 m s–2 = …. km h–2
(d) G = 6.67 × 10–11 N m2 (kg)–2 = …. (cm)3s–2 g–1
Answer:

(c) We know that 1 km = 1000m

So, 1m = 1/1000 km

Then, 3.0 m s-2 = 3.0 (1/1000 km) (1/3600 hour) -2 

= 3.0 x 10-3 km x ((1/3600)-2h-2)

= 3 x 10-3km x (3600)2 hr-2 

Therefore, 3.0 m s-2 = 3.88 x 104 km h­-2

(d) we have => G = 6.67 x 10-11 N m2 (kg)-2

We know that 1N = 1kg m s-2

Where1 kg = 103 g and 1m = 100cm= 102 cm

Putting these values in G, we have :

=> 6.67 x 10-11 Nm2 kg-2 

= 6.67 x 10-11 x (1kg m s -2) (1m2) (1kg-2)

=> 6.67 x 10-11 x (1kg -1 x 1m3 x 1s-2)

Converting kg to g and m to cm, we get –

= 6.67 x 10-11 x (103g)-1 x (102 cm)3 x (1s-2) = 6.67 x 10-8 cm3 s-2 -1

Therefore, G = 6.67 x 10-8  (cm)3 s-2 g -1