A block of mass 30 kg lies on a floor with μs = 0.6 and μk = 0.3. How much force will it take keep the block moving at a constant speed? A.) 1.0 N

B.) 176.4 N

C.) 294.0 N

D.) 88.2 N

waves moving from a fast medium to a slow medium will experience a reflection as light travels more slowly than red light. total internal reflection occurs when the critical angle is.

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg

t = 1/400 h   ⇔ 0.0025 h ⇔ 9s ⇔ 0.15 m

any of the answers are correct.