Question

Can anyone please help me with these.

i've already solved for a just need help on others

In-dass 4-2-20 PE=0] KE=4974 m = 70kg a= S = 120N L a) Speed at bottom of Willis b How much work must to do to I bring sledder to rest "? a Howtar does sledder travel, along flat section, as he comes to rest ? d) Use Newtons 2nd law to find the acceleration of sledder

Answer 1

a) K.E- I muz = 4974 V 20 V= 12 x 4974 ? (2x4974 = 11.92 met 0 m 67 work energy Thorm work done by four change in Kimtic energy initial Kinetic energy K.E;= 49245 final kinetic energy King = mv² = 1 m/0² - 0 as finally sledge is o 2 2 Stoking (= o final whority eo change in Kinetic energy & I KE - KE; / 2 1 0 - 9974 1 = -4974 I negatiu sign chaun that friction is opposing the motion which is obvious way can only tell the magnitude as first part is understood by default is work done by frictional form & fx) = -9974 or = 4974 I I work done = x xd Garu= 128 x d o de 4974 & 41.45 120 m

(do as Fama a= F = m F = fk = 1200 m2 70kg 120 = 1.7143 mi - 2 7-0 retardation a= - 1.71 say as fuis the motion - met2 as there is or we can Ophosing